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<evanfarrar at gmail.com> in [ruby-doc:1382] applied. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@16810 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
1892 lines
64 KiB
Ruby
1892 lines
64 KiB
Ruby
#!/usr/local/bin/ruby -w
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# = csv.rb -- CSV Reading and Writing
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#
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# Created by James Edward Gray II on 2005-10-31.
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# Copyright 2005 James Edward Gray II. You can redistribute or modify this code
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# under the terms of Ruby's license.
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#
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# See CSV for documentation.
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#
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# == Description
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#
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# Welcome to the new and improved CSV.
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#
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# This version of the CSV library began its life as FasterCSV. FasterCSV was
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# intended as a replacement to Ruby's then standard CSV library. It was
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# designed to address concerns users of that library had and it had three
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# primary goals:
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#
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# 1. Be significantly faster than CSV while remaining a pure Ruby library.
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# 2. Use a smaller and easier to maintain code base. (FasterCSV eventually
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# grew larger, was also but considerably richer in features. The parsing
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# core remains quite small.)
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# 3. Improve on the CSV interface.
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#
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# Obviously, the last one is subjective. I did try to defer to the original
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# interface whenever I didn't have a compelling reason to change it though, so
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# hopefully this won't be too radically different.
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#
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# We must have met our goals because FasterCSV was renamed to CSV and replaced
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# the original library.
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#
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# == What's Different From the Old CSV?
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#
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# I'm sure I'll miss something, but I'll try to mention most of the major
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# differences I am aware of, to help others quickly get up to speed:
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#
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# === CSV Parsing
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#
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# * This library has a stricter parser and will throw MalformedCSVErrors on
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# problematic data.
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# * This library has a less liberal idea of a line ending than CSV. What you
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# set as the <tt>:row_sep</tt> is law. It can auto-detect your line endings
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# though.
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# * The old library returned empty lines as <tt>[nil]</tt>. This library calls
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# them <tt>[]</tt>.
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# * This library has a much faster parser.
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#
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# === Interface
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#
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# * CSV now uses Hash-style parameters to set options.
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# * CSV no longer has generate_row() or parse_row().
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# * The old CSV's Reader and Writer classes have been dropped.
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# * CSV::open() is now more like Ruby's open().
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# * CSV objects now support most standard IO methods.
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# * CSV now has a new() method used to wrap objects like String and IO for
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# reading and writing.
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# * CSV::generate() is different from the old method.
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# * CSV no longer supports partial reads. It works line-by-line.
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# * CSV no longer allows the instance methods to override the separators for
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# performance reasons. They must be set in the constructor.
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#
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# If you use this library and find yourself missing any functionality I have
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# trimmed, please {let me know}[mailto:james@grayproductions.net].
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#
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# == Documentation
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#
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# See CSV for documentation.
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#
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# == What is CSV, really?
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#
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# CSV maintains a pretty strict definition of CSV taken directly from
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# {the RFC}[http://www.ietf.org/rfc/rfc4180.txt]. I relax the rules in only one
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# place and that is to make using this library easier. CSV will parse all valid
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# CSV.
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#
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# What you don't want to do is feed CSV invalid data. Because of the way the
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# CSV format works, it's common for a parser to need to read until the end of
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# the file to be sure a field is invalid. This eats a lot of time and memory.
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#
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# Luckily, when working with invalid CSV, Ruby's built-in methods will almost
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# always be superior in every way. For example, parsing non-quoted fields is as
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# easy as:
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#
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# data.split(",")
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#
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# == Questions and/or Comments
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#
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# Feel free to email {James Edward Gray II}[mailto:james@grayproductions.net]
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# with any questions.
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require "forwardable"
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require "English"
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require "enumerator"
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require "date"
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require "stringio"
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#
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# This class provides a complete interface to CSV files and data. It offers
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# tools to enable you to read and write to and from Strings or IO objects, as
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# needed.
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#
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# == Reading
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#
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# === From a File
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#
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# ==== A Line at a Time
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#
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# CSV.foreach("path/to/file.csv") do |row|
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# # use row here...
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# end
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#
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# ==== All at Once
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#
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# arr_of_arrs = CSV.read("path/to/file.csv")
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#
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# === From a String
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#
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# ==== A Line at a Time
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#
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# CSV.parse("CSV,data,String") do |row|
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# # use row here...
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# end
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#
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# ==== All at Once
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#
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# arr_of_arrs = CSV.parse("CSV,data,String")
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#
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# == Writing
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#
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# === To a File
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#
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# CSV.open("path/to/file.csv", "w") do |csv|
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# csv << ["row", "of", "CSV", "data"]
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# csv << ["another", "row"]
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# # ...
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# end
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#
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# === To a String
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#
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# csv_string = CSV.generate do |csv|
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# csv << ["row", "of", "CSV", "data"]
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# csv << ["another", "row"]
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# # ...
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# end
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#
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# == Convert a Single Line
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#
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# csv_string = ["CSV", "data"].to_csv # to CSV
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# csv_array = "CSV,String".parse_csv # from CSV
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#
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# == Shortcut Interface
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#
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# CSV { |csv_out| csv_out << %w{my data here} } # to $stdout
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# CSV(csv = "") { |csv_str| csv_str << %w{my data here} } # to a String
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# CSV($stderr) { |csv_err| csv_err << %w{my data here} } # to $stderr
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#
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class CSV
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# The version of the installed library.
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VERSION = "2.0.0".freeze
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#
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# A CSV::Row is part Array and part Hash. It retains an order for the fields
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# and allows duplicates just as an Array would, but also allows you to access
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# fields by name just as you could if they were in a Hash.
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#
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# All rows returned by CSV will be constructed from this class, if header row
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# processing is activated.
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#
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class Row
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#
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# Construct a new CSV::Row from +headers+ and +fields+, which are expected
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# to be Arrays. If one Array is shorter than the other, it will be padded
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# with +nil+ objects.
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#
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# The optional +header_row+ parameter can be set to +true+ to indicate, via
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# CSV::Row.header_row?() and CSV::Row.field_row?(), that this is a header
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# row. Otherwise, the row is assumes to be a field row.
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#
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# A CSV::Row object supports the following Array methods through delegation:
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#
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# * empty?()
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# * length()
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# * size()
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#
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def initialize(headers, fields, header_row = false)
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@header_row = header_row
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# handle extra headers or fields
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@row = if headers.size > fields.size
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headers.each_with_index.map { |header, i| [header, fields[i]] }
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else
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fields.each_with_index.map { |field, i| [headers[i], field] }
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end
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end
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# Internal data format used to compare equality.
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attr_reader :row
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protected :row
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### Array Delegation ###
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extend Forwardable
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def_delegators :@row, :empty?, :length, :size
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# Returns +true+ if this is a header row.
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def header_row?
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@header_row
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end
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# Returns +true+ if this is a field row.
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def field_row?
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not header_row?
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end
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# Returns the headers of this row.
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def headers
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@row.map { |pair| pair.first }
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end
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#
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# :call-seq:
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# field( header )
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# field( header, offset )
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# field( index )
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#
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# This method will fetch the field value by +header+ or +index+. If a field
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# is not found, +nil+ is returned.
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#
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# When provided, +offset+ ensures that a header match occurrs on or later
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# than the +offset+ index. You can use this to find duplicate headers,
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# without resorting to hard-coding exact indices.
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#
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def field(header_or_index, minimum_index = 0)
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# locate the pair
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finder = header_or_index.is_a?(Integer) ? :[] : :assoc
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pair = @row[minimum_index..-1].send(finder, header_or_index)
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# return the field if we have a pair
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pair.nil? ? nil : pair.last
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end
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alias_method :[], :field
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#
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# :call-seq:
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# []=( header, value )
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# []=( header, offset, value )
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# []=( index, value )
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#
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# Looks up the field by the semantics described in CSV::Row.field() and
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# assigns the +value+.
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#
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# Assigning past the end of the row with an index will set all pairs between
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# to <tt>[nil, nil]</tt>. Assigning to an unused header appends the new
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# pair.
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#
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def []=(*args)
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value = args.pop
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if args.first.is_a? Integer
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if @row[args.first].nil? # extending past the end with index
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@row[args.first] = [nil, value]
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@row.map! { |pair| pair.nil? ? [nil, nil] : pair }
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else # normal index assignment
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@row[args.first][1] = value
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end
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else
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index = index(*args)
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if index.nil? # appending a field
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self << [args.first, value]
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else # normal header assignment
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@row[index][1] = value
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end
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end
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end
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#
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# :call-seq:
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# <<( field )
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# <<( header_and_field_array )
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# <<( header_and_field_hash )
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#
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# If a two-element Array is provided, it is assumed to be a header and field
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# and the pair is appended. A Hash works the same way with the key being
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# the header and the value being the field. Anything else is assumed to be
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# a lone field which is appended with a +nil+ header.
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#
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# This method returns the row for chaining.
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#
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def <<(arg)
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if arg.is_a?(Array) and arg.size == 2 # appending a header and name
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@row << arg
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elsif arg.is_a?(Hash) # append header and name pairs
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arg.each { |pair| @row << pair }
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else # append field value
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@row << [nil, arg]
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end
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self # for chaining
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end
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#
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# A shortcut for appending multiple fields. Equivalent to:
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#
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# args.each { |arg| csv_row << arg }
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#
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# This method returns the row for chaining.
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#
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def push(*args)
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args.each { |arg| self << arg }
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self # for chaining
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end
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#
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# :call-seq:
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# delete( header )
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# delete( header, offset )
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# delete( index )
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#
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# Used to remove a pair from the row by +header+ or +index+. The pair is
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# located as described in CSV::Row.field(). The deleted pair is returned,
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# or +nil+ if a pair could not be found.
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#
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def delete(header_or_index, minimum_index = 0)
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if header_or_index.is_a? Integer # by index
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@row.delete_at(header_or_index)
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else # by header
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@row.delete_at(index(header_or_index, minimum_index))
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end
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end
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#
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# The provided +block+ is passed a header and field for each pair in the row
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# and expected to return +true+ or +false+, depending on whether the pair
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# should be deleted.
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#
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# This method returns the row for chaining.
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#
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def delete_if(&block)
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@row.delete_if(&block)
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self # for chaining
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end
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#
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# This method accepts any number of arguments which can be headers, indices,
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# Ranges of either, or two-element Arrays containing a header and offset.
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# Each argument will be replaced with a field lookup as described in
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# CSV::Row.field().
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#
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# If called with no arguments, all fields are returned.
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#
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def fields(*headers_and_or_indices)
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if headers_and_or_indices.empty? # return all fields--no arguments
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@row.map { |pair| pair.last }
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else # or work like values_at()
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headers_and_or_indices.inject(Array.new) do |all, h_or_i|
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all + if h_or_i.is_a? Range
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index_begin = h_or_i.begin.is_a?(Integer) ? h_or_i.begin :
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index(h_or_i.begin)
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index_end = h_or_i.end.is_a?(Integer) ? h_or_i.end :
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index(h_or_i.end)
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new_range = h_or_i.exclude_end? ? (index_begin...index_end) :
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(index_begin..index_end)
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fields.values_at(new_range)
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else
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[field(*Array(h_or_i))]
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end
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end
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end
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end
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alias_method :values_at, :fields
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#
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# :call-seq:
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# index( header )
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# index( header, offset )
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#
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# This method will return the index of a field with the provided +header+.
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# The +offset+ can be used to locate duplicate header names, as described in
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# CSV::Row.field().
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#
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def index(header, minimum_index = 0)
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# find the pair
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index = headers[minimum_index..-1].index(header)
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# return the index at the right offset, if we found one
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index.nil? ? nil : index + minimum_index
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end
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# Returns +true+ if +name+ is a header for this row, and +false+ otherwise.
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def header?(name)
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headers.include? name
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end
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alias_method :include?, :header?
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#
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# Returns +true+ if +data+ matches a field in this row, and +false+
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# otherwise.
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#
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def field?(data)
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fields.include? data
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end
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include Enumerable
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#
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# Yields each pair of the row as header and field tuples (much like
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# iterating over a Hash).
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#
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# Support for Enumerable.
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#
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# This method returns the row for chaining.
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#
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def each(&block)
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@row.each(&block)
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self # for chaining
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end
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#
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# Returns +true+ if this row contains the same headers and fields in the
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# same order as +other+.
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#
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def ==(other)
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@row == other.row
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end
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#
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# Collapses the row into a simple Hash. Be warning that this discards field
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# order and clobbers duplicate fields.
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#
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def to_hash
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# flatten just one level of the internal Array
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Hash[*@row.inject(Array.new) { |ary, pair| ary.push(*pair) }]
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end
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#
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# Returns the row as a CSV String. Headers are not used. Equivalent to:
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#
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# csv_row.fields.to_csv( options )
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#
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def to_csv(options = Hash.new)
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fields.to_csv(options)
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end
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alias_method :to_s, :to_csv
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end
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#
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# A CSV::Table is a two-dimensional data structure for representing CSV
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# documents. Tables allow you to work with the data by row or column,
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# manipulate the data, and even convert the results back to CSV, if needed.
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#
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# All tables returned by CSV will be constructed from this class, if header
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# row processing is activated.
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#
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class Table
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#
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# Construct a new CSV::Table from +array_of_rows+, which are expected
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# to be CSV::Row objects. All rows are assumed to have the same headers.
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#
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# A CSV::Table object supports the following Array methods through
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# delegation:
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#
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# * empty?()
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# * length()
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# * size()
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#
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def initialize(array_of_rows)
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@table = array_of_rows
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@mode = :col_or_row
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end
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# The current access mode for indexing and iteration.
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attr_reader :mode
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# Internal data format used to compare equality.
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attr_reader :table
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protected :table
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### Array Delegation ###
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extend Forwardable
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def_delegators :@table, :empty?, :length, :size
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#
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# Returns a duplicate table object, in column mode. This is handy for
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# chaining in a single call without changing the table mode, but be aware
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# that this method can consume a fair amount of memory for bigger data sets.
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#
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# This method returns the duplicate table for chaining. Don't chain
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# destructive methods (like []=()) this way though, since you are working
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# with a duplicate.
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#
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def by_col
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self.class.new(@table.dup).by_col!
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end
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#
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# Switches the mode of this table to column mode. All calls to indexing and
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# iteration methods will work with columns until the mode is changed again.
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#
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# This method returns the table and is safe to chain.
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#
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def by_col!
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@mode = :col
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self
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end
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#
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# Returns a duplicate table object, in mixed mode. This is handy for
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# chaining in a single call without changing the table mode, but be aware
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# that this method can consume a fair amount of memory for bigger data sets.
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#
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# This method returns the duplicate table for chaining. Don't chain
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# destructive methods (like []=()) this way though, since you are working
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# with a duplicate.
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#
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def by_col_or_row
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self.class.new(@table.dup).by_col_or_row!
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end
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|
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#
|
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# Switches the mode of this table to mixed mode. All calls to indexing and
|
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# iteration methods will use the default intelligent indexing system until
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# the mode is changed again. In mixed mode an index is assumed to be a row
|
|
# reference while anything else is assumed to be column access by headers.
|
|
#
|
|
# This method returns the table and is safe to chain.
|
|
#
|
|
def by_col_or_row!
|
|
@mode = :col_or_row
|
|
|
|
self
|
|
end
|
|
|
|
#
|
|
# Returns a duplicate table object, in row mode. This is handy for chaining
|
|
# in a single call without changing the table mode, but be aware that this
|
|
# method can consume a fair amount of memory for bigger data sets.
|
|
#
|
|
# This method returns the duplicate table for chaining. Don't chain
|
|
# destructive methods (like []=()) this way though, since you are working
|
|
# with a duplicate.
|
|
#
|
|
def by_row
|
|
self.class.new(@table.dup).by_row!
|
|
end
|
|
|
|
#
|
|
# Switches the mode of this table to row mode. All calls to indexing and
|
|
# iteration methods will work with rows until the mode is changed again.
|
|
#
|
|
# This method returns the table and is safe to chain.
|
|
#
|
|
def by_row!
|
|
@mode = :row
|
|
|
|
self
|
|
end
|
|
|
|
#
|
|
# Returns the headers for the first row of this table (assumed to match all
|
|
# other rows). An empty Array is returned for empty tables.
|
|
#
|
|
def headers
|
|
if @table.empty?
|
|
Array.new
|
|
else
|
|
@table.first.headers
|
|
end
|
|
end
|
|
|
|
#
|
|
# In the default mixed mode, this method returns rows for index access and
|
|
# columns for header access. You can force the index association by first
|
|
# calling by_col!() or by_row!().
|
|
#
|
|
# Columns are returned as an Array of values. Altering that Array has no
|
|
# effect on the table.
|
|
#
|
|
def [](index_or_header)
|
|
if @mode == :row or # by index
|
|
(@mode == :col_or_row and index_or_header.is_a? Integer)
|
|
@table[index_or_header]
|
|
else # by header
|
|
@table.map { |row| row[index_or_header] }
|
|
end
|
|
end
|
|
|
|
#
|
|
# In the default mixed mode, this method assigns rows for index access and
|
|
# columns for header access. You can force the index association by first
|
|
# calling by_col!() or by_row!().
|
|
#
|
|
# Rows may be set to an Array of values (which will inherit the table's
|
|
# headers()) or a CSV::Row.
|
|
#
|
|
# Columns may be set to a single value, which is copied to each row of the
|
|
# column, or an Array of values. Arrays of values are assigned to rows top
|
|
# to bottom in row major order. Excess values are ignored and if the Array
|
|
# does not have a value for each row the extra rows will receive a +nil+.
|
|
#
|
|
# Assigning to an existing column or row clobbers the data. Assigning to
|
|
# new columns creates them at the right end of the table.
|
|
#
|
|
def []=(index_or_header, value)
|
|
if @mode == :row or # by index
|
|
(@mode == :col_or_row and index_or_header.is_a? Integer)
|
|
if value.is_a? Array
|
|
@table[index_or_header] = Row.new(headers, value)
|
|
else
|
|
@table[index_or_header] = value
|
|
end
|
|
else # set column
|
|
if value.is_a? Array # multiple values
|
|
@table.each_with_index do |row, i|
|
|
if row.header_row?
|
|
row[index_or_header] = index_or_header
|
|
else
|
|
row[index_or_header] = value[i]
|
|
end
|
|
end
|
|
else # repeated value
|
|
@table.each do |row|
|
|
if row.header_row?
|
|
row[index_or_header] = index_or_header
|
|
else
|
|
row[index_or_header] = value
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
#
|
|
# The mixed mode default is to treat a list of indices as row access,
|
|
# returning the rows indicated. Anything else is considered columnar
|
|
# access. For columnar access, the return set has an Array for each row
|
|
# with the values indicated by the headers in each Array. You can force
|
|
# column or row mode using by_col!() or by_row!().
|
|
#
|
|
# You cannot mix column and row access.
|
|
#
|
|
def values_at(*indices_or_headers)
|
|
if @mode == :row or # by indices
|
|
( @mode == :col_or_row and indices_or_headers.all? do |index|
|
|
index.is_a?(Integer) or
|
|
( index.is_a?(Range) and
|
|
index.first.is_a?(Integer) and
|
|
index.last.is_a?(Integer) )
|
|
end )
|
|
@table.values_at(*indices_or_headers)
|
|
else # by headers
|
|
@table.map { |row| row.values_at(*indices_or_headers) }
|
|
end
|
|
end
|
|
|
|
#
|
|
# Adds a new row to the bottom end of this table. You can provide an Array,
|
|
# which will be converted to a CSV::Row (inheriting the table's headers()),
|
|
# or a CSV::Row.
|
|
#
|
|
# This method returns the table for chaining.
|
|
#
|
|
def <<(row_or_array)
|
|
if row_or_array.is_a? Array # append Array
|
|
@table << Row.new(headers, row_or_array)
|
|
else # append Row
|
|
@table << row_or_array
|
|
end
|
|
|
|
self # for chaining
|
|
end
|
|
|
|
#
|
|
# A shortcut for appending multiple rows. Equivalent to:
|
|
#
|
|
# rows.each { |row| self << row }
|
|
#
|
|
# This method returns the table for chaining.
|
|
#
|
|
def push(*rows)
|
|
rows.each { |row| self << row }
|
|
|
|
self # for chaining
|
|
end
|
|
|
|
#
|
|
# Removes and returns the indicated column or row. In the default mixed
|
|
# mode indices refer to rows and everything else is assumed to be a column
|
|
# header. Use by_col!() or by_row!() to force the lookup.
|
|
#
|
|
def delete(index_or_header)
|
|
if @mode == :row or # by index
|
|
(@mode == :col_or_row and index_or_header.is_a? Integer)
|
|
@table.delete_at(index_or_header)
|
|
else # by header
|
|
@table.map { |row| row.delete(index_or_header).last }
|
|
end
|
|
end
|
|
|
|
#
|
|
# Removes any column or row for which the block returns +true+. In the
|
|
# default mixed mode or row mode, iteration is the standard row major
|
|
# walking of rows. In column mode, interation will +yield+ two element
|
|
# tuples containing the column name and an Array of values for that column.
|
|
#
|
|
# This method returns the table for chaining.
|
|
#
|
|
def delete_if(&block)
|
|
if @mode == :row or @mode == :col_or_row # by index
|
|
@table.delete_if(&block)
|
|
else # by header
|
|
to_delete = Array.new
|
|
headers.each_with_index do |header, i|
|
|
to_delete << header if block[[header, self[header]]]
|
|
end
|
|
to_delete.map { |header| delete(header) }
|
|
end
|
|
|
|
self # for chaining
|
|
end
|
|
|
|
include Enumerable
|
|
|
|
#
|
|
# In the default mixed mode or row mode, iteration is the standard row major
|
|
# walking of rows. In column mode, interation will +yield+ two element
|
|
# tuples containing the column name and an Array of values for that column.
|
|
#
|
|
# This method returns the table for chaining.
|
|
#
|
|
def each(&block)
|
|
if @mode == :col
|
|
headers.each { |header| block[[header, self[header]]] }
|
|
else
|
|
@table.each(&block)
|
|
end
|
|
|
|
self # for chaining
|
|
end
|
|
|
|
# Returns +true+ if all rows of this table ==() +other+'s rows.
|
|
def ==(other)
|
|
@table == other.table
|
|
end
|
|
|
|
#
|
|
# Returns the table as an Array of Arrays. Headers will be the first row,
|
|
# then all of the field rows will follow.
|
|
#
|
|
def to_a
|
|
@table.inject([headers]) do |array, row|
|
|
if row.header_row?
|
|
array
|
|
else
|
|
array + [row.fields]
|
|
end
|
|
end
|
|
end
|
|
|
|
#
|
|
# Returns the table as a complete CSV String. Headers will be listed first,
|
|
# then all of the field rows.
|
|
#
|
|
def to_csv(options = Hash.new)
|
|
@table.inject([headers.to_csv(options)]) do |rows, row|
|
|
if row.header_row?
|
|
rows
|
|
else
|
|
rows + [row.fields.to_csv(options)]
|
|
end
|
|
end.join
|
|
end
|
|
alias_method :to_s, :to_csv
|
|
end
|
|
|
|
# The error thrown when the parser encounters illegal CSV formatting.
|
|
class MalformedCSVError < RuntimeError; end
|
|
|
|
#
|
|
# A FieldInfo Struct contains details about a field's position in the data
|
|
# source it was read from. CSV will pass this Struct to some blocks that make
|
|
# decisions based on field structure. See CSV.convert_fields() for an
|
|
# example.
|
|
#
|
|
# <b><tt>index</tt></b>:: The zero-based index of the field in its row.
|
|
# <b><tt>line</tt></b>:: The line of the data source this row is from.
|
|
# <b><tt>header</tt></b>:: The header for the column, when available.
|
|
#
|
|
FieldInfo = Struct.new(:index, :line, :header)
|
|
|
|
# A Regexp used to find and convert some common Date formats.
|
|
DateMatcher = / \A(?: (\w+,?\s+)?\w+\s+\d{1,2},?\s+\d{2,4} |
|
|
\d{4}-\d{2}-\d{2} )\z /x
|
|
# A Regexp used to find and convert some common DateTime formats.
|
|
DateTimeMatcher =
|
|
/ \A(?: (\w+,?\s+)?\w+\s+\d{1,2}\s+\d{1,2}:\d{1,2}:\d{1,2},?\s+\d{2,4} |
|
|
\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2} )\z /x
|
|
#
|
|
# This Hash holds the built-in converters of CSV that can be accessed by name.
|
|
# You can select Converters with CSV.convert() or through the +options+ Hash
|
|
# passed to CSV::new().
|
|
#
|
|
# <b><tt>:integer</tt></b>:: Converts any field Integer() accepts.
|
|
# <b><tt>:float</tt></b>:: Converts any field Float() accepts.
|
|
# <b><tt>:numeric</tt></b>:: A combination of <tt>:integer</tt>
|
|
# and <tt>:float</tt>.
|
|
# <b><tt>:date</tt></b>:: Converts any field Date::parse() accepts.
|
|
# <b><tt>:date_time</tt></b>:: Converts any field DateTime::parse() accepts.
|
|
# <b><tt>:all</tt></b>:: All built-in converters. A combination of
|
|
# <tt>:date_time</tt> and <tt>:numeric</tt>.
|
|
#
|
|
# This Hash is intentionally left unfrozen and users should feel free to add
|
|
# values to it that can be accessed by all CSV objects.
|
|
#
|
|
# To add a combo field, the value should be an Array of names. Combo fields
|
|
# can be nested with other combo fields.
|
|
#
|
|
Converters = { :integer => lambda { |f| Integer(f) rescue f },
|
|
:float => lambda { |f| Float(f) rescue f },
|
|
:numeric => [:integer, :float],
|
|
:date => lambda { |f|
|
|
f =~ DateMatcher ? (Date.parse(f) rescue f) : f
|
|
},
|
|
:date_time => lambda { |f|
|
|
f =~ DateTimeMatcher ? (DateTime.parse(f) rescue f) : f
|
|
},
|
|
:all => [:date_time, :numeric] }
|
|
|
|
#
|
|
# This Hash holds the built-in header converters of CSV that can be accessed
|
|
# by name. You can select HeaderConverters with CSV.header_convert() or
|
|
# through the +options+ Hash passed to CSV::new().
|
|
#
|
|
# <b><tt>:downcase</tt></b>:: Calls downcase() on the header String.
|
|
# <b><tt>:symbol</tt></b>:: The header String is downcased, spaces are
|
|
# replaced with underscores, non-word characters
|
|
# are dropped, and finally to_sym() is called.
|
|
#
|
|
# This Hash is intetionally left unfrozen and users should feel free to add
|
|
# values to it that can be accessed by all CSV objects.
|
|
#
|
|
# To add a combo field, the value should be an Array of names. Combo fields
|
|
# can be nested with other combo fields.
|
|
#
|
|
HeaderConverters = {
|
|
:downcase => lambda { |h| h.downcase },
|
|
:symbol => lambda { |h|
|
|
h.downcase.tr(" ", "_").delete("^a-z0-9_").to_sym
|
|
}
|
|
}
|
|
|
|
#
|
|
# The options used when no overrides are given by calling code. They are:
|
|
#
|
|
# <b><tt>:col_sep</tt></b>:: <tt>","</tt>
|
|
# <b><tt>:row_sep</tt></b>:: <tt>:auto</tt>
|
|
# <b><tt>:quote_char</tt></b>:: <tt>'"'</tt>
|
|
# <b><tt>:converters</tt></b>:: +nil+
|
|
# <b><tt>:unconverted_fields</tt></b>:: +nil+
|
|
# <b><tt>:headers</tt></b>:: +false+
|
|
# <b><tt>:return_headers</tt></b>:: +false+
|
|
# <b><tt>:header_converters</tt></b>:: +nil+
|
|
# <b><tt>:skip_blanks</tt></b>:: +false+
|
|
# <b><tt>:force_quotes</tt></b>:: +false+
|
|
#
|
|
DEFAULT_OPTIONS = { :col_sep => ",",
|
|
:row_sep => :auto,
|
|
:quote_char => '"',
|
|
:converters => nil,
|
|
:unconverted_fields => nil,
|
|
:headers => false,
|
|
:return_headers => false,
|
|
:header_converters => nil,
|
|
:skip_blanks => false,
|
|
:force_quotes => false }.freeze
|
|
|
|
#
|
|
# This method allows you to serialize an Array of Ruby objects to a String or
|
|
# File of CSV data. This is not as powerful as Marshal or YAML, but perhaps
|
|
# useful for spreadsheet and database interaction.
|
|
#
|
|
# Out of the box, this method is intended to work with simple data objects or
|
|
# Structs. It will serialize a list of instance variables and/or
|
|
# Struct.members().
|
|
#
|
|
# If you need need more complicated serialization, you can control the process
|
|
# by adding methods to the class to be serialized.
|
|
#
|
|
# A class method csv_meta() is responsible for returning the first row of the
|
|
# document (as an Array). This row is considered to be a Hash of the form
|
|
# key_1,value_1,key_2,value_2,... CSV::load() expects to find a class key
|
|
# with a value of the stringified class name and CSV::dump() will create this,
|
|
# if you do not define this method. This method is only called on the first
|
|
# object of the Array.
|
|
#
|
|
# The next method you can provide is an instance method called csv_headers().
|
|
# This method is expected to return the second line of the document (again as
|
|
# an Array), which is to be used to give each column a header. By default,
|
|
# CSV::load() will set an instance variable if the field header starts with an
|
|
# @ character or call send() passing the header as the method name and
|
|
# the field value as an argument. This method is only called on the first
|
|
# object of the Array.
|
|
#
|
|
# Finally, you can provide an instance method called csv_dump(), which will
|
|
# be passed the headers. This should return an Array of fields that can be
|
|
# serialized for this object. This method is called once for every object in
|
|
# the Array.
|
|
#
|
|
# The +io+ parameter can be used to serialize to a File, and +options+ can be
|
|
# anything CSV::new() accepts.
|
|
#
|
|
def self.dump(ary_of_objs, io = "", options = Hash.new)
|
|
obj_template = ary_of_objs.first
|
|
|
|
csv = new(io, options)
|
|
|
|
# write meta information
|
|
begin
|
|
csv << obj_template.class.csv_meta
|
|
rescue NoMethodError
|
|
csv << [:class, obj_template.class]
|
|
end
|
|
|
|
# write headers
|
|
begin
|
|
headers = obj_template.csv_headers
|
|
rescue NoMethodError
|
|
headers = obj_template.instance_variables.sort
|
|
if obj_template.class.ancestors.find { |cls| cls.to_s =~ /\AStruct\b/ }
|
|
headers += obj_template.members.map { |mem| "#{mem}=" }.sort
|
|
end
|
|
end
|
|
csv << headers
|
|
|
|
# serialize each object
|
|
ary_of_objs.each do |obj|
|
|
begin
|
|
csv << obj.csv_dump(headers)
|
|
rescue NoMethodError
|
|
csv << headers.map do |var|
|
|
if var[0] == ?@
|
|
obj.instance_variable_get(var)
|
|
else
|
|
obj[var[0..-2]]
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
if io.is_a? String
|
|
csv.string
|
|
else
|
|
csv.close
|
|
end
|
|
end
|
|
|
|
#
|
|
# :call-seq:
|
|
# filter( options = Hash.new ) { |row| ... }
|
|
# filter( input, options = Hash.new ) { |row| ... }
|
|
# filter( input, output, options = Hash.new ) { |row| ... }
|
|
#
|
|
# This method is a convenience for building Unix-like filters for CSV data.
|
|
# Each row is yielded to the provided block which can alter it as needed.
|
|
# After the block returns, the row is appended to +output+ altered or not.
|
|
#
|
|
# The +input+ and +output+ arguments can be anything CSV::new() accepts
|
|
# (generally String or IO objects). If not given, they default to
|
|
# <tt>ARGF</tt> and <tt>$stdout</tt>.
|
|
#
|
|
# The +options+ parameter is also filtered down to CSV::new() after some
|
|
# clever key parsing. Any key beginning with <tt>:in_</tt> or
|
|
# <tt>:input_</tt> will have that leading identifier stripped and will only
|
|
# be used in the +options+ Hash for the +input+ object. Keys starting with
|
|
# <tt>:out_</tt> or <tt>:output_</tt> affect only +output+. All other keys
|
|
# are assigned to both objects.
|
|
#
|
|
# The <tt>:output_row_sep</tt> +option+ defaults to
|
|
# <tt>$INPUT_RECORD_SEPARATOR</tt> (<tt>$/</tt>).
|
|
#
|
|
def self.filter(*args)
|
|
# parse options for input, output, or both
|
|
in_options, out_options = Hash.new, {:row_sep => $INPUT_RECORD_SEPARATOR}
|
|
if args.last.is_a? Hash
|
|
args.pop.each do |key, value|
|
|
case key.to_s
|
|
when /\Ain(?:put)?_(.+)\Z/
|
|
in_options[$1.to_sym] = value
|
|
when /\Aout(?:put)?_(.+)\Z/
|
|
out_options[$1.to_sym] = value
|
|
else
|
|
in_options[key] = value
|
|
out_options[key] = value
|
|
end
|
|
end
|
|
end
|
|
# build input and output wrappers
|
|
input = new(args.shift || ARGF, in_options)
|
|
output = new(args.shift || $stdout, out_options)
|
|
|
|
# read, yield, write
|
|
input.each do |row|
|
|
yield row
|
|
output << row
|
|
end
|
|
end
|
|
|
|
#
|
|
# This method is intended as the primary interface for reading CSV files. You
|
|
# pass a +path+ and any +options+ you wish to set for the read. Each row of
|
|
# file will be passed to the provided +block+ in turn.
|
|
#
|
|
# The +options+ parameter can be anything CSV::new() understands.
|
|
#
|
|
def self.foreach(path, options = Hash.new, &block)
|
|
open(path, options) do |csv|
|
|
csv.each(&block)
|
|
end
|
|
end
|
|
|
|
#
|
|
# :call-seq:
|
|
# generate( str, options = Hash.new ) { |csv| ... }
|
|
# generate( options = Hash.new ) { |csv| ... }
|
|
#
|
|
# This method wraps a String you provide, or an empty default String, in a
|
|
# CSV object which is passed to the provided block. You can use the block to
|
|
# append CSV rows to the String and when the block exits, the final String
|
|
# will be returned.
|
|
#
|
|
# Note that a passed String *is* modfied by this method. Call dup() before
|
|
# passing if you need a new String.
|
|
#
|
|
# The +options+ parameter can be anthing CSV::new() understands.
|
|
#
|
|
def self.generate(*args)
|
|
# add a default empty String, if none was given
|
|
if args.first.is_a? String
|
|
io = StringIO.new(args.shift)
|
|
io.seek(0, IO::SEEK_END)
|
|
args.unshift(io)
|
|
else
|
|
args.unshift("")
|
|
end
|
|
csv = new(*args) # wrap
|
|
yield csv # yield for appending
|
|
csv.string # return final String
|
|
end
|
|
|
|
#
|
|
# This method is a shortcut for converting a single row (Array) into a CSV
|
|
# String.
|
|
#
|
|
# The +options+ parameter can be anthing CSV::new() understands.
|
|
#
|
|
# The <tt>:row_sep</tt> +option+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>
|
|
# (<tt>$/</tt>) when calling this method.
|
|
#
|
|
def self.generate_line(row, options = Hash.new)
|
|
options = {:row_sep => $INPUT_RECORD_SEPARATOR}.merge(options)
|
|
(new("", options) << row).string
|
|
end
|
|
|
|
#
|
|
# This method will return a CSV instance, just like CSV::new(), but the
|
|
# instance will be cached and returned for all future calls to this method for
|
|
# the same +data+ object (tested by Object#object_id()) with the same
|
|
# +options+.
|
|
#
|
|
# If a block is given, the instance is passed to the block and the return
|
|
# value becomes the return value of the block.
|
|
#
|
|
def self.instance(data = $stdout, options = Hash.new)
|
|
# create a _signature_ for this method call, data object and options
|
|
sig = [data.object_id] +
|
|
options.values_at(*DEFAULT_OPTIONS.keys.sort_by { |sym| sym.to_s })
|
|
|
|
# fetch or create the instance for this signature
|
|
@@instances ||= Hash.new
|
|
instance = (@@instances[sig] ||= new(data, options))
|
|
|
|
if block_given?
|
|
yield instance # run block, if given, returning result
|
|
else
|
|
instance # or return the instance
|
|
end
|
|
end
|
|
|
|
#
|
|
# This method is the reading counterpart to CSV::dump(). See that method for
|
|
# a detailed description of the process.
|
|
#
|
|
# You can customize loading by adding a class method called csv_load() which
|
|
# will be passed a Hash of meta information, an Array of headers, and an Array
|
|
# of fields for the object the method is expected to return.
|
|
#
|
|
# Remember that all fields will be Strings after this load. If you need
|
|
# something else, use +options+ to setup converters or provide a custom
|
|
# csv_load() implementation.
|
|
#
|
|
def self.load(io_or_str, options = Hash.new)
|
|
csv = new(io_or_str, options)
|
|
|
|
# load meta information
|
|
meta = Hash[*csv.shift]
|
|
cls = meta["class"].split("::").inject(Object) do |c, const|
|
|
c.const_get(const)
|
|
end
|
|
|
|
# load headers
|
|
headers = csv.shift
|
|
|
|
# unserialize each object stored in the file
|
|
results = csv.inject(Array.new) do |all, row|
|
|
begin
|
|
obj = cls.csv_load(meta, headers, row)
|
|
rescue NoMethodError
|
|
obj = cls.allocate
|
|
headers.zip(row) do |name, value|
|
|
if name[0] == ?@
|
|
obj.instance_variable_set(name, value)
|
|
else
|
|
obj.send(name, value)
|
|
end
|
|
end
|
|
end
|
|
all << obj
|
|
end
|
|
|
|
csv.close unless io_or_str.is_a? String
|
|
|
|
results
|
|
end
|
|
|
|
#
|
|
# :call-seq:
|
|
# open( filename, mode="r", options = Hash.new ) { |csv| ... }
|
|
# open( filename, mode="r", options = Hash.new )
|
|
#
|
|
# This method opens an IO object, and wraps that with CSV. This is intended
|
|
# as the primary interface for writing a CSV file.
|
|
#
|
|
# You may pass any +args+ Ruby's open() understands followed by an optional
|
|
# Hash containing any +options+ CSV::new() understands.
|
|
#
|
|
# This method works like Ruby's open() call, in that it will pass a CSV object
|
|
# to a provided block and close it when the block terminates, or it will
|
|
# return the CSV object when no block is provided. (*Note*: This is different
|
|
# from the Ruby 1.8 CSV library which passed rows to the block. Use
|
|
# CSV::foreach() for that behavior.)
|
|
#
|
|
# An opened CSV object will delegate to many IO methods, for convenience. You
|
|
# may call:
|
|
#
|
|
# * binmode()
|
|
# * close()
|
|
# * close_read()
|
|
# * close_write()
|
|
# * closed?()
|
|
# * eof()
|
|
# * eof?()
|
|
# * fcntl()
|
|
# * fileno()
|
|
# * flush()
|
|
# * fsync()
|
|
# * ioctl()
|
|
# * isatty()
|
|
# * pid()
|
|
# * pos()
|
|
# * reopen()
|
|
# * seek()
|
|
# * stat()
|
|
# * sync()
|
|
# * sync=()
|
|
# * tell()
|
|
# * to_i()
|
|
# * to_io()
|
|
# * tty?()
|
|
#
|
|
def self.open(*args)
|
|
# find the +options+ Hash
|
|
options = if args.last.is_a? Hash then args.pop else Hash.new end
|
|
# wrap a File opened with the remaining +args+
|
|
csv = new(File.open(*args), options)
|
|
|
|
# handle blocks like Ruby's open(), not like the CSV library
|
|
if block_given?
|
|
begin
|
|
yield csv
|
|
ensure
|
|
csv.close
|
|
end
|
|
else
|
|
csv
|
|
end
|
|
end
|
|
|
|
#
|
|
# :call-seq:
|
|
# parse( str, options = Hash.new ) { |row| ... }
|
|
# parse( str, options = Hash.new )
|
|
#
|
|
# This method can be used to easily parse CSV out of a String. You may either
|
|
# provide a +block+ which will be called with each row of the String in turn,
|
|
# or just use the returned Array of Arrays (when no +block+ is given).
|
|
#
|
|
# You pass your +str+ to read from, and an optional +options+ Hash containing
|
|
# anything CSV::new() understands.
|
|
#
|
|
def self.parse(*args, &block)
|
|
csv = new(*args)
|
|
if block.nil? # slurp contents, if no block is given
|
|
begin
|
|
csv.read
|
|
ensure
|
|
csv.close
|
|
end
|
|
else # or pass each row to a provided block
|
|
csv.each(&block)
|
|
end
|
|
end
|
|
|
|
#
|
|
# This method is a shortcut for converting a single line of a CSV String into
|
|
# a into an Array. Note that if +line+ contains multiple rows, anything
|
|
# beyond the first row is ignored.
|
|
#
|
|
# The +options+ parameter can be anthing CSV::new() understands.
|
|
#
|
|
def self.parse_line(line, options = Hash.new)
|
|
new(line, options).shift
|
|
end
|
|
|
|
#
|
|
# Use to slurp a CSV file into an Array of Arrays. Pass the +path+ to the
|
|
# file and any +options+ CSV::new() understands.
|
|
#
|
|
def self.read(path, options = Hash.new)
|
|
open(path, options) { |csv| csv.read }
|
|
end
|
|
|
|
# Alias for CSV::read().
|
|
def self.readlines(*args)
|
|
read(*args)
|
|
end
|
|
|
|
#
|
|
# A shortcut for:
|
|
#
|
|
# CSV.read( path, { :headers => true,
|
|
# :converters => :numeric,
|
|
# :header_converters => :symbol }.merge(options) )
|
|
#
|
|
def self.table(path, options = Hash.new)
|
|
read( path, { :headers => true,
|
|
:converters => :numeric,
|
|
:header_converters => :symbol }.merge(options) )
|
|
end
|
|
|
|
#
|
|
# This constructor will wrap either a String or IO object passed in +data+ for
|
|
# reading and/or writing. In addition to the CSV instance methods, several IO
|
|
# methods are delegated. (See CSV::open() for a complete list.) If you pass
|
|
# a String for +data+, you can later retrieve it (after writing to it, for
|
|
# example) with CSV.string().
|
|
#
|
|
# Note that a wrapped String will be positioned at at the beginning (for
|
|
# reading). If you want it at the end (for writing), use CSV::generate().
|
|
# If you want any other positioning, pass a preset StringIO object instead.
|
|
#
|
|
# You may set any reading and/or writing preferences in the +options+ Hash.
|
|
# Available options are:
|
|
#
|
|
# <b><tt>:col_sep</tt></b>:: The String placed between each field.
|
|
# <b><tt>:row_sep</tt></b>:: The String appended to the end of each
|
|
# row. This can be set to the special
|
|
# <tt>:auto</tt> setting, which requests
|
|
# that CSV automatically discover this
|
|
# from the data. Auto-discovery reads
|
|
# ahead in the data looking for the next
|
|
# <tt>"\r\n"</tt>, <tt>"\n"</tt>, or
|
|
# <tt>"\r"</tt> sequence. A sequence
|
|
# will be selected even if it occurs in
|
|
# a quoted field, assuming that you
|
|
# would have the same line endings
|
|
# there. If none of those sequences is
|
|
# found, +data+ is <tt>ARGF</tt>,
|
|
# <tt>STDIN</tt>, <tt>STDOUT</tt>, or
|
|
# <tt>STDERR</tt>, or the stream is only
|
|
# available for output, the default
|
|
# <tt>$INPUT_RECORD_SEPARATOR</tt>
|
|
# (<tt>$/</tt>) is used. Obviously,
|
|
# discovery takes a little time. Set
|
|
# manually if speed is important.
|
|
# <b><tt>:quote_char</tt></b>:: The character used to quote fields.
|
|
# This has to be a single character
|
|
# String. This is useful for
|
|
# application that incorrectly use
|
|
# <tt>'</tt> as the quote character
|
|
# instead of the correct <tt>"</tt>.
|
|
# CSV will always consider a double
|
|
# sequence this character to be an
|
|
# escaped quote.
|
|
# <b><tt>:converters</tt></b>:: An Array of names from the Converters
|
|
# Hash and/or lambdas that handle custom
|
|
# conversion. A single converter
|
|
# doesn't have to be in an Array.
|
|
# <b><tt>:unconverted_fields</tt></b>:: If set to +true+, an
|
|
# unconverted_fields() method will be
|
|
# added to all returned rows (Array or
|
|
# CSV::Row) that will return the fields
|
|
# as they were before conversion. Note
|
|
# that <tt>:headers</tt> supplied by
|
|
# Array or String were not fields of the
|
|
# document and thus will have an empty
|
|
# Array attached.
|
|
# <b><tt>:headers</tt></b>:: If set to <tt>:first_row</tt> or
|
|
# +true+, the initial row of the CSV
|
|
# file will be treated as a row of
|
|
# headers. If set to an Array, the
|
|
# contents will be used as the headers.
|
|
# If set to a String, the String is run
|
|
# through a call of CSV::parse_line() to
|
|
# produce an Array of headers. This
|
|
# setting causes CSV.shift() to return
|
|
# rows as CSV::Row objects instead of
|
|
# Arrays and CSV.read() to return
|
|
# CSV::Table objects instead of an Array
|
|
# of Arrays.
|
|
# <b><tt>:return_headers</tt></b>:: When +false+, header rows are silently
|
|
# swallowed. If set to +true+, header
|
|
# rows are returned in a CSV::Row object
|
|
# with identical headers and
|
|
# fields (save that the fields do not go
|
|
# through the converters).
|
|
# <b><tt>:header_converters</tt></b>:: Identical in functionality to
|
|
# <tt>:converters</tt> save that the
|
|
# conversions are only made to header
|
|
# rows.
|
|
# <b><tt>:skip_blanks</tt></b>:: When set to a +true+ value, CSV will
|
|
# skip over any rows with no content.
|
|
# <b><tt>:force_quotes</tt></b>:: When set to a +true+ value, CSV will
|
|
# quote all CSV fields it creates.
|
|
#
|
|
# See CSV::DEFAULT_OPTIONS for the default settings.
|
|
#
|
|
# Options cannot be overriden in the instance methods for performance reasons,
|
|
# so be sure to set what you want here.
|
|
#
|
|
def initialize(data, options = Hash.new)
|
|
# build the options for this read/write
|
|
options = DEFAULT_OPTIONS.merge(options)
|
|
|
|
# create the IO object we will read from
|
|
@io = if data.is_a? String then StringIO.new(data) else data end
|
|
|
|
init_separators(options)
|
|
init_parsers(options)
|
|
init_converters(options)
|
|
init_headers(options)
|
|
|
|
unless options.empty?
|
|
raise ArgumentError, "Unknown options: #{options.keys.join(', ')}."
|
|
end
|
|
|
|
# track our own lineno since IO gets confused about line-ends is CSV fields
|
|
@lineno = 0
|
|
end
|
|
|
|
#
|
|
# The line number of the last row read from this file. Fields with nested
|
|
# line-end characters will not affect this count.
|
|
#
|
|
attr_reader :lineno
|
|
|
|
### IO and StringIO Delegation ###
|
|
|
|
extend Forwardable
|
|
def_delegators :@io, :binmode, :close, :close_read, :close_write, :closed?,
|
|
:eof, :eof?, :fcntl, :fileno, :flush, :fsync, :ioctl,
|
|
:isatty, :pid, :pos, :reopen, :seek, :stat, :string,
|
|
:sync, :sync=, :tell, :to_i, :to_io, :tty?
|
|
|
|
# Rewinds the underlying IO object and resets CSV's lineno() counter.
|
|
def rewind
|
|
@headers = nil
|
|
@lineno = 0
|
|
|
|
@io.rewind
|
|
end
|
|
|
|
### End Delegation ###
|
|
|
|
#
|
|
# The primary write method for wrapped Strings and IOs, +row+ (an Array or
|
|
# CSV::Row) is converted to CSV and appended to the data source. When a
|
|
# CSV::Row is passed, only the row's fields() are appended to the output.
|
|
#
|
|
# The data source must be open for writing.
|
|
#
|
|
def <<(row)
|
|
# handle CSV::Row objects and Hashes
|
|
row = case row
|
|
when self.class::Row then row.fields
|
|
when Hash then @headers.map { |header| row[header] }
|
|
else row
|
|
end
|
|
|
|
@headers = row if header_row?
|
|
@lineno += 1
|
|
|
|
@io << row.map(&@quote).join(@col_sep) + @row_sep # quote and separate
|
|
|
|
self # for chaining
|
|
end
|
|
alias_method :add_row, :<<
|
|
alias_method :puts, :<<
|
|
|
|
#
|
|
# :call-seq:
|
|
# convert( name )
|
|
# convert { |field| ... }
|
|
# convert { |field, field_info| ... }
|
|
#
|
|
# You can use this method to install a CSV::Converters built-in, or provide a
|
|
# block that handles a custom conversion.
|
|
#
|
|
# If you provide a block that takes one argument, it will be passed the field
|
|
# and is expected to return the converted value or the field itself. If your
|
|
# block takes two arguments, it will also be passed a FieldInfo Struct,
|
|
# containing details about the field. Again, the block should return a
|
|
# converted field or the field itself.
|
|
#
|
|
def convert(name = nil, &converter)
|
|
add_converter(:converters, self.class::Converters, name, &converter)
|
|
end
|
|
|
|
#
|
|
# :call-seq:
|
|
# header_convert( name )
|
|
# header_convert { |field| ... }
|
|
# header_convert { |field, field_info| ... }
|
|
#
|
|
# Identical to CSV.convert(), but for header rows.
|
|
#
|
|
# Note that this method must be called before header rows are read to have any
|
|
# effect.
|
|
#
|
|
def header_convert(name = nil, &converter)
|
|
add_converter( :header_converters,
|
|
self.class::HeaderConverters,
|
|
name,
|
|
&converter )
|
|
end
|
|
|
|
include Enumerable
|
|
|
|
#
|
|
# Yields each row of the data source in turn.
|
|
#
|
|
# Support for Enumerable.
|
|
#
|
|
# The data source must be open for reading.
|
|
#
|
|
def each
|
|
while row = shift
|
|
yield row
|
|
end
|
|
end
|
|
|
|
#
|
|
# Slurps the remaining rows and returns an Array of Arrays.
|
|
#
|
|
# The data source must be open for reading.
|
|
#
|
|
def read
|
|
rows = to_a
|
|
if @use_headers
|
|
Table.new(rows)
|
|
else
|
|
rows
|
|
end
|
|
end
|
|
alias_method :readlines, :read
|
|
|
|
# Returns +true+ if the next row read will be a header row.
|
|
def header_row?
|
|
@use_headers and @headers.nil?
|
|
end
|
|
|
|
#
|
|
# The primary read method for wrapped Strings and IOs, a single row is pulled
|
|
# from the data source, parsed and returned as an Array of fields (if header
|
|
# rows are not used) or a CSV::Row (when header rows are used).
|
|
#
|
|
# The data source must be open for reading.
|
|
#
|
|
def shift
|
|
#########################################################################
|
|
### This method is purposefully kept a bit long as simple conditional ###
|
|
### checks are faster than numerous (expensive) method calls. ###
|
|
#########################################################################
|
|
|
|
# handle headers not based on document content
|
|
if header_row? and @return_headers and
|
|
[Array, String].include? @use_headers.class
|
|
if @unconverted_fields
|
|
return add_unconverted_fields(parse_headers, Array.new)
|
|
else
|
|
return parse_headers
|
|
end
|
|
end
|
|
|
|
# begin with a blank line, so we can always add to it
|
|
line = ""
|
|
|
|
#
|
|
# it can take multiple calls to <tt>@io.gets()</tt> to get a full line,
|
|
# because of \r and/or \n characters embedded in quoted fields
|
|
#
|
|
loop do
|
|
# add another read to the line
|
|
(line += @io.gets(@row_sep)) rescue return nil
|
|
# copy the line so we can chop it up in parsing
|
|
parse = line.dup
|
|
parse.sub!(@parsers[:line_end], "")
|
|
|
|
#
|
|
# I believe a blank line should be an <tt>Array.new</tt>, not Ruby 1.8
|
|
# CSV's <tt>[nil]</tt>
|
|
#
|
|
if parse.empty?
|
|
@lineno += 1
|
|
if @skip_blanks
|
|
line = ""
|
|
next
|
|
elsif @unconverted_fields
|
|
return add_unconverted_fields(Array.new, Array.new)
|
|
elsif @use_headers
|
|
return self.class::Row.new(Array.new, Array.new)
|
|
else
|
|
return Array.new
|
|
end
|
|
end
|
|
|
|
#
|
|
# shave leading empty fields if needed, because the main parser chokes
|
|
# on these
|
|
#
|
|
csv = if parse.sub!(@parsers[:leading_fields], "")
|
|
[nil] * ($&.length / @col_sep.length)
|
|
else
|
|
Array.new
|
|
end
|
|
#
|
|
# then parse the main fields with a hyper-tuned Regexp from
|
|
# Mastering Regular Expressions, Second Edition
|
|
#
|
|
parse.gsub!(@parsers[:csv_row]) do
|
|
csv << if $1.nil? # we found an unquoted field
|
|
if $2.empty? # switch empty unquoted fields to +nil+...
|
|
nil # for Ruby 1.8 CSV compatibility
|
|
else
|
|
# I decided to take a strict approach to CSV parsing...
|
|
if $2.count("\r\n").zero? # verify correctness of field...
|
|
$2
|
|
else
|
|
# or throw an Exception
|
|
raise MalformedCSVError, "Unquoted fields do not allow " +
|
|
"\\r or \\n (line #{lineno + 1})."
|
|
end
|
|
end
|
|
else # we found a quoted field...
|
|
$1.gsub(@quote_char * 2, @quote_char) # unescape contents
|
|
end
|
|
"" # gsub!'s replacement, clear the field
|
|
end
|
|
|
|
# if parse is empty?(), we found all the fields on the line...
|
|
if parse.empty?
|
|
@lineno += 1
|
|
|
|
# save fields unconverted fields, if needed...
|
|
unconverted = csv.dup if @unconverted_fields
|
|
|
|
# convert fields, if needed...
|
|
csv = convert_fields(csv) unless @use_headers or @converters.empty?
|
|
# parse out header rows and handle CSV::Row conversions...
|
|
csv = parse_headers(csv) if @use_headers
|
|
|
|
# inject unconverted fields and accessor, if requested...
|
|
if @unconverted_fields and not csv.respond_to? :unconverted_fields
|
|
add_unconverted_fields(csv, unconverted)
|
|
end
|
|
|
|
# return the results
|
|
break csv
|
|
end
|
|
# if we're not empty?() but at eof?(), a quoted field wasn't closed...
|
|
if @io.eof?
|
|
raise MalformedCSVError, "Unclosed quoted field on line #{lineno + 1}."
|
|
end
|
|
# otherwise, we need to loop and pull some more data to complete the row
|
|
end
|
|
end
|
|
alias_method :gets, :shift
|
|
alias_method :readline, :shift
|
|
|
|
private
|
|
|
|
#
|
|
# Stores the indicated separators for later use.
|
|
#
|
|
# If auto-discovery was requested for <tt>@row_sep</tt>, this method will read
|
|
# ahead in the <tt>@io</tt> and try to find one. +ARGF+, +STDIN+, +STDOUT+,
|
|
# +STDERR+ and any stream open for output only with a default
|
|
# <tt>@row_sep</tt> of <tt>$INPUT_RECORD_SEPARATOR</tt> (<tt>$/</tt>).
|
|
#
|
|
# This method also establishes the quoting rules used for CSV output.
|
|
#
|
|
def init_separators(options)
|
|
# store the selected separators
|
|
@col_sep = options.delete(:col_sep)
|
|
@row_sep = options.delete(:row_sep)
|
|
@quote_char = options.delete(:quote_char)
|
|
|
|
if @quote_char.length != 1
|
|
raise ArgumentError, ":quote_char has to be a single character String"
|
|
end
|
|
|
|
# automatically discover row separator when requested
|
|
if @row_sep == :auto
|
|
if [ARGF, STDIN, STDOUT, STDERR].include?(@io) or
|
|
(defined?(Zlib) and @io.class == Zlib::GzipWriter)
|
|
@row_sep = $INPUT_RECORD_SEPARATOR
|
|
else
|
|
begin
|
|
saved_pos = @io.pos # remember where we were
|
|
while @row_sep == :auto
|
|
#
|
|
# if we run out of data, it's probably a single line
|
|
# (use a sensible default)
|
|
#
|
|
if @io.eof?
|
|
@row_sep = $INPUT_RECORD_SEPARATOR
|
|
break
|
|
end
|
|
|
|
# read ahead a bit
|
|
sample = @io.read(1024)
|
|
sample += @io.read(1) if sample[-1..-1] == "\r" and not @io.eof?
|
|
|
|
# try to find a standard separator
|
|
if sample =~ /\r\n?|\n/
|
|
@row_sep = $&
|
|
break
|
|
end
|
|
end
|
|
# tricky seek() clone to work around GzipReader's lack of seek()
|
|
@io.rewind
|
|
# reset back to the remembered position
|
|
while saved_pos > 1024 # avoid loading a lot of data into memory
|
|
@io.read(1024)
|
|
saved_pos -= 1024
|
|
end
|
|
@io.read(saved_pos) if saved_pos.nonzero?
|
|
rescue IOError # stream not opened for reading
|
|
@row_sep = $INPUT_RECORD_SEPARATOR
|
|
end
|
|
end
|
|
end
|
|
|
|
# establish quoting rules
|
|
do_quote = lambda do |field|
|
|
@quote_char +
|
|
String(field).gsub(@quote_char, @quote_char * 2) +
|
|
@quote_char
|
|
end
|
|
@quote = if options.delete(:force_quotes)
|
|
do_quote
|
|
else
|
|
lambda do |field|
|
|
if field.nil? # represent +nil+ fields as empty unquoted fields
|
|
""
|
|
else
|
|
field = String(field) # Stringify fields
|
|
# represent empty fields as empty quoted fields
|
|
if field.empty? or
|
|
field.count("\r\n#{@col_sep}#{@quote_char}").nonzero?
|
|
do_quote.call(field)
|
|
else
|
|
field # unquoted field
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
# Pre-compiles parsers and stores them by name for access during reads.
|
|
def init_parsers(options)
|
|
# store the parser behaviors
|
|
@skip_blanks = options.delete(:skip_blanks)
|
|
|
|
# prebuild Regexps for faster parsing
|
|
esc_col_sep = Regexp.escape(@col_sep)
|
|
esc_row_sep = Regexp.escape(@row_sep)
|
|
esc_quote = Regexp.escape(@quote_char)
|
|
@parsers = {
|
|
:leading_fields =>
|
|
/\A(?:#{esc_col_sep})+/, # for empty leading fields
|
|
:csv_row =>
|
|
### The Primary Parser ###
|
|
/ \G(?:^|#{esc_col_sep}) # anchor the match
|
|
(?: #{esc_quote}( (?>[^#{esc_quote}]*) # find quoted fields
|
|
(?> #{esc_quote*2}
|
|
[^#{esc_quote}]* )* )#{esc_quote}
|
|
| # ... or ...
|
|
([^#{esc_quote}#{esc_col_sep}]*) # unquoted fields
|
|
)/x,
|
|
### End Primary Parser ###
|
|
:line_end =>
|
|
/#{esc_row_sep}\z/ # safer than chomp!()
|
|
}
|
|
end
|
|
|
|
#
|
|
# Loads any converters requested during construction.
|
|
#
|
|
# If +field_name+ is set <tt>:converters</tt> (the default) field converters
|
|
# are set. When +field_name+ is <tt>:header_converters</tt> header converters
|
|
# are added instead.
|
|
#
|
|
# The <tt>:unconverted_fields</tt> option is also actived for
|
|
# <tt>:converters</tt> calls, if requested.
|
|
#
|
|
def init_converters(options, field_name = :converters)
|
|
if field_name == :converters
|
|
@unconverted_fields = options.delete(:unconverted_fields)
|
|
end
|
|
|
|
instance_variable_set("@#{field_name}", Array.new)
|
|
|
|
# find the correct method to add the converters
|
|
convert = method(field_name.to_s.sub(/ers\Z/, ""))
|
|
|
|
# load converters
|
|
unless options[field_name].nil?
|
|
# allow a single converter not wrapped in an Array
|
|
unless options[field_name].is_a? Array
|
|
options[field_name] = [options[field_name]]
|
|
end
|
|
# load each converter...
|
|
options[field_name].each do |converter|
|
|
if converter.is_a? Proc # custom code block
|
|
convert.call(&converter)
|
|
else # by name
|
|
convert.call(converter)
|
|
end
|
|
end
|
|
end
|
|
|
|
options.delete(field_name)
|
|
end
|
|
|
|
# Stores header row settings and loads header converters, if needed.
|
|
def init_headers(options)
|
|
@use_headers = options.delete(:headers)
|
|
@return_headers = options.delete(:return_headers)
|
|
|
|
# headers must be delayed until shift(), in case they need a row of content
|
|
@headers = nil
|
|
|
|
init_converters(options, :header_converters)
|
|
end
|
|
|
|
#
|
|
# The actual work method for adding converters, used by both CSV.convert() and
|
|
# CSV.header_convert().
|
|
#
|
|
# This method requires the +var_name+ of the instance variable to place the
|
|
# converters in, the +const+ Hash to lookup named converters in, and the
|
|
# normal parameters of the CSV.convert() and CSV.header_convert() methods.
|
|
#
|
|
def add_converter(var_name, const, name = nil, &converter)
|
|
if name.nil? # custom converter
|
|
instance_variable_get("@#{var_name}") << converter
|
|
else # named converter
|
|
combo = const[name]
|
|
case combo
|
|
when Array # combo converter
|
|
combo.each do |converter_name|
|
|
add_converter(var_name, const, converter_name)
|
|
end
|
|
else # individual named converter
|
|
instance_variable_get("@#{var_name}") << combo
|
|
end
|
|
end
|
|
end
|
|
|
|
#
|
|
# Processes +fields+ with <tt>@converters</tt>, or <tt>@header_converters</tt>
|
|
# if +headers+ is passed as +true+, returning the converted field set. Any
|
|
# converter that changes the field into something other than a String halts
|
|
# the pipeline of conversion for that field. This is primarily an efficiency
|
|
# shortcut.
|
|
#
|
|
def convert_fields(fields, headers = false)
|
|
# see if we are converting headers or fields
|
|
converters = headers ? @header_converters : @converters
|
|
|
|
fields.each_with_index.map do |field, index| # map_with_index
|
|
converters.each do |converter|
|
|
field = if converter.arity == 1 # straight field converter
|
|
converter[field]
|
|
else # FieldInfo converter
|
|
header = @use_headers && !headers ? @headers[index] : nil
|
|
converter[field, FieldInfo.new(index, lineno, header)]
|
|
end
|
|
break unless field.is_a? String # short-curcuit pipeline for speed
|
|
end
|
|
field # final state of each field, converted or original
|
|
end
|
|
end
|
|
|
|
#
|
|
# This methods is used to turn a finished +row+ into a CSV::Row. Header rows
|
|
# are also dealt with here, either by returning a CSV::Row with identical
|
|
# headers and fields (save that the fields do not go through the converters)
|
|
# or by reading past them to return a field row. Headers are also saved in
|
|
# <tt>@headers</tt> for use in future rows.
|
|
#
|
|
# When +nil+, +row+ is assumed to be a header row not based on an actual row
|
|
# of the stream.
|
|
#
|
|
def parse_headers(row = nil)
|
|
if @headers.nil? # header row
|
|
@headers = case @use_headers # save headers
|
|
when Array then @use_headers # Array of headers
|
|
when String then self.class.parse_line(@use_headers) # CSV header String
|
|
else row # first row headers
|
|
end
|
|
|
|
# prepare converted and unconverted copies
|
|
row = @headers if row.nil?
|
|
@headers = convert_fields(@headers, true)
|
|
|
|
if @return_headers # return headers
|
|
return self.class::Row.new(@headers, row, true)
|
|
elsif not [Array, String].include? @use_headers.class # skip to field row
|
|
return shift
|
|
end
|
|
end
|
|
|
|
self.class::Row.new(@headers, convert_fields(row)) # field row
|
|
end
|
|
|
|
#
|
|
# Thiw methods injects an instance variable <tt>unconverted_fields</tt> into
|
|
# +row+ and an accessor method for it called unconverted_fields(). The
|
|
# variable is set to the contents of +fields+.
|
|
#
|
|
def add_unconverted_fields(row, fields)
|
|
class << row
|
|
attr_reader :unconverted_fields
|
|
end
|
|
row.instance_eval { @unconverted_fields = fields }
|
|
row
|
|
end
|
|
end
|
|
|
|
# Another name for CSV::instance().
|
|
def CSV(*args, &block)
|
|
CSV.instance(*args, &block)
|
|
end
|
|
|
|
class Array
|
|
# Equivalent to <tt>CSV::generate_line(self, options)</tt>.
|
|
def to_csv(options = Hash.new)
|
|
CSV.generate_line(self, options)
|
|
end
|
|
end
|
|
|
|
class String
|
|
# Equivalent to <tt>CSV::parse_line(self, options)</tt>.
|
|
def parse_csv(options = Hash.new)
|
|
CSV.parse_line(self, options)
|
|
end
|
|
end
|