Current File : //opt/alt/ruby19/lib64/ruby/1.9.1/ripper/lexer.rb
#
# $Id: lexer.rb 45158 2014-02-24 03:43:27Z usa $
#
# Copyright (c) 2004,2005 Minero Aoki
#
# This program is free software.
# You can distribute and/or modify this program under the Ruby License.
# For details of Ruby License, see ruby/COPYING.
#
require 'ripper/core'
class Ripper
# Tokenizes the Ruby program and returns an array of strings.
#
# p Ripper.tokenize("def m(a) nil end")
# # => ["def", " ", "m", "(", "a", ")", " ", "nil", " ", "end"]
#
def Ripper.tokenize(src, filename = '-', lineno = 1)
Lexer.new(src, filename, lineno).tokenize
end
# Tokenizes the Ruby program and returns an array of an array,
# which is formatted like <code>[[lineno, column], type, token]</code>.
#
# require 'ripper'
# require 'pp'
#
# p Ripper.lex("def m(a) nil end")
# #=> [[[1, 0], :on_kw, "def"],
# [[1, 3], :on_sp, " " ],
# [[1, 4], :on_ident, "m" ],
# [[1, 5], :on_lparen, "(" ],
# [[1, 6], :on_ident, "a" ],
# [[1, 7], :on_rparen, ")" ],
# [[1, 8], :on_sp, " " ],
# [[1, 9], :on_kw, "nil"],
# [[1, 12], :on_sp, " " ],
# [[1, 13], :on_kw, "end"]]
#
def Ripper.lex(src, filename = '-', lineno = 1)
Lexer.new(src, filename, lineno).lex
end
class Lexer < ::Ripper #:nodoc: internal use only
def tokenize
lex().map {|pos, event, tok| tok }
end
def lex
parse().sort_by {|pos, event, tok| pos }
end
def parse
@buf = []
super
@buf
end
private
SCANNER_EVENTS.each do |event|
module_eval(<<-End, __FILE__+'/module_eval', __LINE__ + 1)
def on_#{event}(tok)
@buf.push [[lineno(), column()], :on_#{event}, tok]
end
End
end
end
# [EXPERIMENTAL]
# Parses +src+ and return a string which was matched to +pattern+.
# +pattern+ should be described as Regexp.
#
# require 'ripper'
#
# p Ripper.slice('def m(a) nil end', 'ident') #=> "m"
# p Ripper.slice('def m(a) nil end', '[ident lparen rparen]+') #=> "m(a)"
# p Ripper.slice("<<EOS\nstring\nEOS",
# 'heredoc_beg nl $(tstring_content*) heredoc_end', 1)
# #=> "string\n"
#
def Ripper.slice(src, pattern, n = 0)
if m = token_match(src, pattern)
then m.string(n)
else nil
end
end
def Ripper.token_match(src, pattern) #:nodoc:
TokenPattern.compile(pattern).match(src)
end
class TokenPattern #:nodoc:
class Error < ::StandardError; end
class CompileError < Error; end
class MatchError < Error; end
class << self
alias compile new
end
def initialize(pattern)
@source = pattern
@re = compile(pattern)
end
def match(str)
match_list(::Ripper.lex(str))
end
def match_list(tokens)
if m = @re.match(map_tokens(tokens))
then MatchData.new(tokens, m)
else nil
end
end
private
def compile(pattern)
if m = /[^\w\s$()\[\]{}?*+\.]/.match(pattern)
raise CompileError, "invalid char in pattern: #{m[0].inspect}"
end
buf = ''
pattern.scan(/(?:\w+|\$\(|[()\[\]\{\}?*+\.]+)/) do |tok|
case tok
when /\w/
buf.concat map_token(tok)
when '$('
buf.concat '('
when '('
buf.concat '(?:'
when /[?*\[\])\.]/
buf.concat tok
else
raise 'must not happen'
end
end
Regexp.compile(buf)
rescue RegexpError => err
raise CompileError, err.message
end
def map_tokens(tokens)
tokens.map {|pos,type,str| map_token(type.to_s.sub(/\Aon_/,'')) }.join
end
MAP = {}
seed = ('a'..'z').to_a + ('A'..'Z').to_a + ('0'..'9').to_a
SCANNER_EVENT_TABLE.each do |ev, |
raise CompileError, "[RIPPER FATAL] too many system token" if seed.empty?
MAP[ev.to_s.sub(/\Aon_/,'')] = seed.shift
end
def map_token(tok)
MAP[tok] or raise CompileError, "unknown token: #{tok}"
end
class MatchData
def initialize(tokens, match)
@tokens = tokens
@match = match
end
def string(n = 0)
return nil unless @match
match(n).join
end
private
def match(n = 0)
return [] unless @match
@tokens[@match.begin(n)...@match.end(n)].map {|pos,type,str| str }
end
end
end
end