Module: Regexp::Lexer
- Defined in:
- lib/regexp_parser/lexer.rb
Overview
A very thin wrapper around the scanner that breaks quantified literal runs, collects emitted tokens into an array, calculates their nesting depth, and normalizes tokens for the parser, and checks if they are implemented by the given syntax flavor.
Constant Summary collapse
- OPENING_TOKENS =
[:capture, :options, :passive, :atomic, :named, :lookahead, :nlookahead, :lookbehind, :nlookbehind ].freeze
- CLOSING_TOKENS =
[:close].freeze
Class Method Summary collapse
Class Method Details
.lex(input, syntax = "ruby/#{RUBY_VERSION}", &block) ⇒ Object Also known as: scan
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# File 'lib/regexp_parser/lexer.rb', line 13 def self.lex(input, syntax = "ruby/#{RUBY_VERSION}", &block) syntax = Regexp::Syntax.new(syntax) @tokens = [] @nesting, @set_nesting, @conditional_nesting = 0, 0, 0 last = nil Regexp::Scanner.scan(input) do |type, token, text, ts, te| type, token = *syntax.normalize(type, token) syntax.check! type, token ascend(type, token) break_literal(last) if type == :quantifier and last and last.type == :literal current = Regexp::Token.new(type, token, text, ts, te, @nesting, @set_nesting, @conditional_nesting) current = merge_literal(current) if type == :literal and last and last.type == :literal current = merge_condition(current) if type == :conditional and [:condition, :condition_close].include?(token) last.next(current) if last current.previous(last) if last @tokens << current last = current descend(type, token) end if block_given? @tokens.map {|t| block.call(t)} else @tokens end end |