1 # ----------------------------------------------------------------------------- 2 # hedit.py 3 # 4 # Paring of Fortran H Edit descriptions (Contributed by Pearu Peterson) 5 # 6 # These tokens can't be easily tokenized because they are of the following 7 # form: 8 # 9 # nHc1...cn 10 # 11 # where n is a positive integer and c1 ... cn are characters. 12 # 13 # This example shows how to modify the state of the lexer to parse 14 # such tokens 15 # ----------------------------------------------------------------------------- 16 import sys 17 if ".." not in sys.path: sys.path.insert(0,"..") 18 19 import ply.lex as lex 20 21 tokens = ( 22 'H_EDIT_DESCRIPTOR', 23 ) 24 25 # Tokens 26 t_ignore = " \t\n" 27 28 def t_H_EDIT_DESCRIPTOR(t): 29 r"\d+H.*" # This grabs all of the remaining text 30 i = t.value.index('H') 31 n = eval(t.value[:i]) 32 33 # Adjust the tokenizing position 34 t.lexer.lexpos -= len(t.value) - (i+1+n) 35 t.value = t.value[i+1:i+1+n] 36 return t 37 38 def t_error(t): 39 print("Illegal character '%s'" % t.value[0]) 40 t.lexer.skip(1) 41 42 # Build the lexer 43 lex.lex() 44 lex.runmain(data="3Habc 10Habcdefghij 2Hxy") 45 46 47 48
