|
|
- # ply: ygen.py
- #
- # This is a support program that auto-generates different versions of the YACC parsing
- # function with different features removed for the purposes of performance.
- #
- # Users should edit the method LRParser.parsedebug() in yacc.py. The source code
- # for that method is then used to create the other methods. See the comments in
- # yacc.py for further details.
-
- import os.path
- import shutil
-
- def get_source_range(lines, tag):
- srclines = enumerate(lines)
- start_tag = '#--! %s-start' % tag
- end_tag = '#--! %s-end' % tag
-
- for start_index, line in srclines:
- if line.strip().startswith(start_tag):
- break
-
- for end_index, line in srclines:
- if line.strip().endswith(end_tag):
- break
-
- return (start_index + 1, end_index)
-
- def filter_section(lines, tag):
- filtered_lines = []
- include = True
- tag_text = '#--! %s' % tag
- for line in lines:
- if line.strip().startswith(tag_text):
- include = not include
- elif include:
- filtered_lines.append(line)
- return filtered_lines
-
- def main():
- dirname = os.path.dirname(__file__)
- shutil.copy2(os.path.join(dirname, 'yacc.py'), os.path.join(dirname, 'yacc.py.bak'))
- with open(os.path.join(dirname, 'yacc.py'), 'r') as f:
- lines = f.readlines()
-
- parse_start, parse_end = get_source_range(lines, 'parsedebug')
- parseopt_start, parseopt_end = get_source_range(lines, 'parseopt')
- parseopt_notrack_start, parseopt_notrack_end = get_source_range(lines, 'parseopt-notrack')
-
- # Get the original source
- orig_lines = lines[parse_start:parse_end]
-
- # Filter the DEBUG sections out
- parseopt_lines = filter_section(orig_lines, 'DEBUG')
-
- # Filter the TRACKING sections out
- parseopt_notrack_lines = filter_section(parseopt_lines, 'TRACKING')
-
- # Replace the parser source sections with updated versions
- lines[parseopt_notrack_start:parseopt_notrack_end] = parseopt_notrack_lines
- lines[parseopt_start:parseopt_end] = parseopt_lines
-
- lines = [line.rstrip()+'\n' for line in lines]
- with open(os.path.join(dirname, 'yacc.py'), 'w') as f:
- f.writelines(lines)
-
- print('Updated yacc.py')
-
- if __name__ == '__main__':
- main()
|
