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cca61dafe8
+:void_stmt+ is meaningless [Bug #6929] [ruby-core:47507] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36992 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
73 lines
2.5 KiB
Ruby
73 lines
2.5 KiB
Ruby
require 'ripper/core'
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require 'ripper/lexer'
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require 'ripper/filter'
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require 'ripper/sexp'
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# Ripper is a Ruby script parser.
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#
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# You can get information from the parser with event-based style.
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# Information such as abstract syntax trees or simple lexical analysis of the
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# Ruby program.
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#
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# == Usage
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#
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# Ripper provides an easy interface for parsing your program into a symbolic
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# expression tree (or S-expression).
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#
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# Understanding the output of the parser may come as a challenge, it's
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# recommended you use PP to format the output for legibility.
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#
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# require 'ripper'
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# require 'pp'
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#
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# pp Ripper.sexp('def hello(world) "Hello, #{world}!"; end')
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# #=> [:program,
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# [[:def,
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# [:@ident, "hello", [1, 4]],
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# [:paren,
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# [:params, [[:@ident, "world", [1, 10]]], nil, nil, nil, nil]],
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# [:bodystmt,
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# [[:string_literal,
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# [:string_content,
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# [:@tstring_content, "Hello, ", [1, 18]],
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# [:string_embexpr, [[:var_ref, [:@ident, "world", [1, 27]]]]],
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# [:@tstring_content, "!", [1, 33]]]]],
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# nil,
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# nil,
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# nil]]]]
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#
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# You can see in the example above, the expression starts with +:program+.
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#
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# From here, a method definition at +:def+, followed by the method's identifier
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# <code>:@ident</code>. After the method's identifier comes the parentheses
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# +:paren+ and the method parameters under +:params+.
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#
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# Next is the method body, starting at +:bodystmt+ (+stmt+ meaning statement),
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# which contains the full definition of the method.
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#
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# In our case, we're simply returning a String, so next we have the
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# +:string_literal+ expression.
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#
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# Within our +:string_literal+ you'll notice two <code>@tstring_content</code>,
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# this is the literal part for <code>Hello, </code> and <code>!</code>. Between
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# the two <code>@tstring_content</code> statements is a +:string_embexpr+,
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# where _embexpr_ is an embedded expression. Our expression consists of a local
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# variable, or +var_ref+, with the identifier (<code>@ident</code>) of +world+.
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#
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# == Resources
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#
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# * {Ruby Inside}[http://www.rubyinside.com/using-ripper-to-see-how-ruby-is-parsing-your-code-5270.html]
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#
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# == Requirements
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#
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# * ruby 1.9 (support CVS HEAD only)
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# * bison 1.28 or later (Other yaccs do not work)
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#
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# == License
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#
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# Ruby License.
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#
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# Minero Aoki
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# aamine@loveruby.net
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# http://i.loveruby.net
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class Ripper; end
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