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Diffstat (limited to 'util/sconfig/yappsrt.py')
| -rw-r--r-- | util/sconfig/yappsrt.py | 172 |
1 files changed, 0 insertions, 172 deletions
diff --git a/util/sconfig/yappsrt.py b/util/sconfig/yappsrt.py deleted file mode 100644 index 2ce2480f08..0000000000 --- a/util/sconfig/yappsrt.py +++ /dev/null @@ -1,172 +0,0 @@ -# Yapps 2.0 Runtime -# -# This module is needed to run generated parsers. - -from string import * -import exceptions -import re - -class SyntaxError(Exception): - """When we run into an unexpected token, this is the exception to use""" - def __init__(self, pos=-1, msg="Bad Token"): - self.pos = pos - self.msg = msg - def __repr__(self): - if self.pos < 0: return "#<syntax-error>" - else: return "SyntaxError[@ char " + `self.pos` + ": " + self.msg + "]" - -class NoMoreTokens(Exception): - """Another exception object, for when we run out of tokens""" - pass - -class Scanner: - def __init__(self, patterns, ignore, input): - """Patterns is [(terminal,regex)...] - Ignore is [terminal,...]; - Input is a string""" - self.tokens = [] - self.restrictions = [] - self.input = input - self.pos = 0 - self.ignore = ignore - # The stored patterns are a pair (compiled regex,source - # regex). If the patterns variable passed in to the - # constructor is None, we assume that the class already has a - # proper .patterns list constructed - if patterns is not None: - self.patterns = [] - for k,r in patterns: - self.patterns.append( (k, re.compile(r)) ) - - def token(self, i, restrict=0): - """Get the i'th token, and if i is one past the end, then scan - for another token; restrict is a list of tokens that - are allowed, or 0 for any token.""" - if i == len(self.tokens): self.scan(restrict) - if i < len(self.tokens): - # Make sure the restriction is more restricted - if restrict and self.restrictions[i]: - for r in restrict: - if r not in self.restrictions[i]: - raise "Unimplemented: restriction set changed" - return self.tokens[i] - raise NoMoreTokens() - - def __repr__(self): - """Print the last 10 tokens that have been scanned in""" - output = '' - for t in self.tokens[-10:]: - output = '%s\n (@%s) %s = %s' % (output,t[0],t[2],`t[3]`) - return output - - def scan(self, restrict): - """Should scan another token and add it to the list, self.tokens, - and add the restriction to self.restrictions""" - # Keep looking for a token, ignoring any in self.ignore - while 1: - # Search the patterns for the longest match, with earlier - # tokens in the list having preference - best_match = -1 - best_pat = '(error)' - for p, regexp in self.patterns: - # First check to see if we're ignoring this token - if restrict and p not in restrict and p not in self.ignore: - continue - m = regexp.match(self.input, self.pos) - if m and len(m.group(0)) > best_match: - # We got a match that's better than the previous one - best_pat = p - best_match = len(m.group(0)) - - # If we didn't find anything, raise an error - if best_pat == '(error)' and best_match < 0: - msg = "Bad Token" - if restrict: - msg = "Trying to find one of "+join(restrict,", ") - raise SyntaxError(self.pos, msg) - - # If we found something that isn't to be ignored, return it - if best_pat not in self.ignore: - # Create a token with this data - token = (self.pos, self.pos+best_match, best_pat, - self.input[self.pos:self.pos+best_match]) - self.pos = self.pos + best_match - # Only add this token if it's not in the list - # (to prevent looping) - if not self.tokens or token != self.tokens[-1]: - self.tokens.append(token) - self.restrictions.append(restrict) - return - else: - # This token should be ignored .. - self.pos = self.pos + best_match - -class Parser: - def __init__(self, scanner): - self._scanner = scanner - self._pos = 0 - - def _peek(self, *types): - """Returns the token type for lookahead; if there are any args - then the list of args is the set of token types to allow""" - tok = self._scanner.token(self._pos, types) - return tok[2] - - def _scan(self, type): - """Returns the matched text, and moves to the next token""" - tok = self._scanner.token(self._pos, [type]) - if tok[2] != type: - raise SyntaxError(tok[0], 'Trying to find '+type) - self._pos = 1+self._pos - return tok[3] - - - -def print_error(input, err, scanner): - """This is a really dumb long function to print error messages nicely.""" - p = err.pos - # Figure out the line number - line = count(input[:p], '\n') - print err.msg+" on line "+`line+1`+":" - # Now try printing part of the line - text = input[max(p-80,0):p+80] - p = p - max(p-80,0) - - # Strip to the left - i = rfind(text[:p],'\n') - j = rfind(text[:p],'\r') - if i < 0 or (j < i and j >= 0): i = j - if i >= 0 and i < p: - p = p - i - 1 - text = text[i+1:] - - # Strip to the right - i = find(text,'\n',p) - j = find(text,'\r',p) - if i < 0 or (j < i and j >= 0): i = j - if i >= 0: - text = text[:i] - - # Now shorten the text - while len(text) > 70 and p > 60: - # Cut off 10 chars - text = "..." + text[10:] - p = p - 7 - - # Now print the string, along with an indicator - print '> ',text - print '> ',' '*p + '^' - print 'List of nearby tokens:', scanner - -def wrap_error_reporter(parser, rule): - try: return getattr(parser, rule)() - except SyntaxError, s: - input = parser._scanner.input - try: - print_error(input, s, parser._scanner) - except ImportError: - print 'Syntax Error',s.msg,'on line',1+count(input[:s.pos], '\n') - except NoMoreTokens: - print 'Could not complete parsing; stopped around here:' - print parser._scanner - |