Files
linguist/lib/linguist/tokenizer.rb
2012-06-08 14:46:16 -05:00

117 lines
2.4 KiB
Ruby

module Linguist
# Generic programming language tokenizer.
#
# Tokens are designed for use in the language bayes classifier.
# It strips any data strings or comments and preserves significant
# language symbols.
class Tokenizer
def initialize(data)
@data = data
end
# Get source data.
#
# Returns String.
attr_reader :data
# Extract tokens from data.
#
# Returns Array of Strings.
def tokens
extract_tokens(data)
end
def extract_tokens(data)
s = StringScanner.new(data)
tokens = []
until s.eos?
# Ruby single line comment
if token = s.scan(/# /)
tokens << "#"
s.skip_until(/\n|\Z/)
# C style single line comment
elsif token = s.scan(/\/\/ /)
tokens << "//"
s.skip_until(/\n|\Z/)
# C multiline comments
elsif token = s.scan(/\/\*/)
tokens << "/*"
s.skip_until(/\*\//)
tokens << "*/"
# Haskell multiline comments
elsif token = s.scan(/\{-/)
tokens << "{-"
s.skip_until(/-\}/)
tokens << "-}"
# XML multiline comments
elsif token = s.scan(/<!--/)
tokens << "<!--"
s.skip_until(/-->/)
tokens << "-->"
elsif s.scan(/"/)
s.skip_until(/[^\\]"/)
elsif s.scan(/'/)
s.skip_until(/[^\\]'/)
# SGML style brackets
elsif token = s.scan(/<[^>]+>/)
extract_sgml_tokens(token).each { |t| tokens << t }
# Common programming punctuation
elsif token = s.scan(/;|\{|\}|\(|\)|<<?/)
tokens << token
# Regular token
elsif token = s.scan(/[\w\.@#\/]+/)
tokens << token
else
s.getch
end
end
tokens
end
def extract_sgml_tokens(data)
s = StringScanner.new(data)
tokens = []
until s.eos?
if token = s.scan(/<\/?[^\s>]+/)
tokens << "#{token}>"
elsif token = s.scan(/\w+=/)
tokens << token
if s.scan(/"/)
s.skip_until(/[^\\]"/)
elsif s.scan(/'/)
s.skip_until(/[^\\]'/)
else
s.skip_until(/\w+/)
end
elsif token = s.scan(/\w+/)
tokens << token
elsif s.scan(/>/)
s.terminate
else
s.getch
end
end
tokens
end
end
end