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