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+# lexer for yacc-grammars
+#
+# Author: David Beazley (dave@dabeaz.com)
+# Date : October 2, 2006
+
+import sys
+sys.path.append("../..")
+
+from ply import *
+
+tokens = (
+ 'LITERAL','SECTION','TOKEN','LEFT','RIGHT','PREC','START','TYPE','NONASSOC','UNION','CODE',
+ 'ID','QLITERAL','NUMBER',
+)
+
+states = (('code','exclusive'),)
+
+literals = [ ';', ',', '<', '>', '|',':' ]
+t_ignore = ' \t'
+
+t_TOKEN = r'%token'
+t_LEFT = r'%left'
+t_RIGHT = r'%right'
+t_NONASSOC = r'%nonassoc'
+t_PREC = r'%prec'
+t_START = r'%start'
+t_TYPE = r'%type'
+t_UNION = r'%union'
+t_ID = r'[a-zA-Z_][a-zA-Z_0-9]*'
+t_QLITERAL = r'''(?P<quote>['"]).*?(?P=quote)'''
+t_NUMBER = r'\d+'
+
+def t_SECTION(t):
+ r'%%'
+ if getattr(t.lexer,"lastsection",0):
+ t.value = t.lexer.lexdata[t.lexpos+2:]
+ t.lexer.lexpos = len(t.lexer.lexdata)
+ else:
+ t.lexer.lastsection = 0
+ return t
+
+# Comments
+def t_ccomment(t):
+ r'/\*(.|\n)*?\*/'
+ t.lineno += t.value.count('\n')
+
+t_ignore_cppcomment = r'//.*'
+
+def t_LITERAL(t):
+ r'%\{(.|\n)*?%\}'
+ t.lexer.lineno += t.value.count("\n")
+ return t
+
+def t_NEWLINE(t):
+ r'\n'
+ t.lexer.lineno += 1
+
+def t_code(t):
+ r'\{'
+ t.lexer.codestart = t.lexpos
+ t.lexer.level = 1
+ t.lexer.begin('code')
+
+def t_code_ignore_string(t):
+ r'\"([^\\\n]|(\\.))*?\"'
+
+def t_code_ignore_char(t):
+ r'\'([^\\\n]|(\\.))*?\''
+
+def t_code_ignore_comment(t):
+ r'/\*(.|\n)*?\*/'
+
+def t_code_ignore_cppcom(t):
+ r'//.*'
+
+def t_code_lbrace(t):
+ r'\{'
+ t.lexer.level += 1
+
+def t_code_rbrace(t):
+ r'\}'
+ t.lexer.level -= 1
+ if t.lexer.level == 0:
+ t.type = 'CODE'
+ t.value = t.lexer.lexdata[t.lexer.codestart:t.lexpos+1]
+ t.lexer.begin('INITIAL')
+ t.lexer.lineno += t.value.count('\n')
+ return t
+
+t_code_ignore_nonspace = r'[^\s\}\'\"\{]+'
+t_code_ignore_whitespace = r'\s+'
+t_code_ignore = ""
+
+def t_code_error(t):
+ raise RuntimeError
+
+def t_error(t):
+ print "%d: Illegal character '%s'" % (t.lineno, t.value[0])
+ print t.value
+ t.lexer.skip(1)
+
+lex.lex()
+
+if __name__ == '__main__':
+ lex.runmain()
+
+
+
+
+
+
+