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ruby--ruby/doc/csv/options/parsing/headers.rdoc

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====== Option +headers+
Specifies a boolean, \Symbol, \Array, or \String to be used
to define column headers.
Default value:
CSV::DEFAULT_OPTIONS.fetch(:headers) # => false
---
Without +headers+:
str = <<-EOT
Name,Count
foo,0
bar,1
bax,2
EOT
csv = CSV.new(str)
csv # => #<CSV io_type:StringIO encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\"">
csv.headers # => nil
csv.shift # => ["Name", "Count"]
---
If set to +true+ or the \Symbol +:first_row+,
the first row of the data is treated as a row of headers:
str = <<-EOT
Name,Count
foo,0
bar,1
bax,2
EOT
csv = CSV.new(str, headers: true)
csv # => #<CSV io_type:StringIO encoding:UTF-8 lineno:2 col_sep:"," row_sep:"\n" quote_char:"\"" headers:["Name", "Count"]>
csv.headers # => ["Name", "Count"]
csv.shift # => #<CSV::Row "Name":"bar" "Count":"1">
---
If set to an \Array, the \Array elements are treated as headers:
str = <<-EOT
foo,0
bar,1
bax,2
EOT
csv = CSV.new(str, headers: ['Name', 'Count'])
csv
csv.headers # => ["Name", "Count"]
csv.shift # => #<CSV::Row "Name":"bar" "Count":"1">
---
If set to a \String +str+, method <tt>CSV::parse_line(str, options)</tt> is called
with the current +options+, and the returned \Array is treated as headers:
str = <<-EOT
foo,0
bar,1
bax,2
EOT
csv = CSV.new(str, headers: 'Name,Count')
csv
csv.headers # => ["Name", "Count"]
csv.shift # => #<CSV::Row "Name":"bar" "Count":"1">