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9b7fe0a250
Currently, parse.y actions are hard to read and write because the code
has double meaning (for core parser and for ripper). I think that, if
it is easy to write ripper's code shortly and simply, the double meaning
trick is not needed.
For the sake, this change adds a simple DSL for ripper's code. For
example, in parse.y, we can write:
/*% ripper: stmts_add(stmts_new, void_stmt) %*/
instead of:
$$ = dispatch2(stmts_add, dispatch0(stmts_new),
dispatch0(void_stmt));
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61952 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
46 lines
952 B
Ruby
46 lines
952 B
Ruby
# Simple DSL implementation for Ripper code generation
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#
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# input: /*% ripper: stmts_add(stmts_new, void_stmt) %*/
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# output: $$ = dispatch2(stmts_add, dispatch0(stmts_new), dispatch0(void_stmt))
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class DSL
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def initialize(code, options)
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@events = {}
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@error = options.include?("error")
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@brace = options.include?("brace")
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# create $1 == "$1", $2 == "$2", ...
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re, s = "", ""
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1.upto(9) do |n|
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re << "(..)"
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s << "$#{ n }"
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end
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/#{ re }/ =~ s
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@code = eval(code)
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end
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attr_reader :events
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undef lambda
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undef hash
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undef class
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def generate
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s = "$$"
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s = "\t\t\t#{ s } = #@code;"
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s << "ripper_error(p);" if @error
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s = "{#{ s }}" if @brace
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s
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end
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def method_missing(*args)
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if args.first =~ /\A_/
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"#{ $' }(#{ args.drop(1).join(", ") })"
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else
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@events[args.first.to_s] = args.size - 1
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"dispatch#{ args.size - 1 }(#{ args.join(", ") })"
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end
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end
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end
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