def parseImpl(self, string, loc, doActions=True):
maxExcLoc = -1
maxException = None
matches = []
for e in self.exprs:
try:
loc2 = e.tryParse(string, loc)
except ParseException as err:
err.__traceback__ = None
if err.loc > maxExcLoc:
maxException = err
maxExcLoc = err.loc
except IndexError:
if len(string) > maxExcLoc:
maxException = ParseException(string, len(string), self)
maxExcLoc = len(string)
else:
# save match among all matches, to retry longest to shortest
matches.append((loc2, e))
if matches:
# re-evaluate all matches in descending order of length of match, in case attached actions
# might change whether or how much they match of the input.
matches.sort(key=itemgetter(0), reverse=True)
if not doActions:
# no further conditions or parse actions to change the selection of
# alternative, so the first match will be the best match
_, best_expr = matches[0]
loc, best_results = best_expr._parse(string, loc, doActions)
return loc, ParseResults(self, [best_results])
longest = -1, None
for loc1, expr1 in matches:
if loc1 <= longest[0]:
# already have a longer match than this one will deliver, we are done
return longest
try:
loc2, toks = expr1._parse(string, loc, doActions)
except ParseException as err:
err.__traceback__ = None
if err.loc > maxExcLoc:
maxException = err
maxExcLoc = err.loc
else:
if loc2 >= loc1:
return loc2, ParseResults(self, [toks])
# didn't match as much as before
elif loc2 > longest[0]:
longest = loc2, ParseResults(self, [toks])
if longest != (-1, None):
return longest
if maxException is not None:
maxException.msg = "Expecting " + text(self)
raise maxException
else:
raise ParseException(string, loc, "no defined alternatives to match", self)
def parseImpl(self, string, loc, doActions=True):
maxExcLoc = -1
maxException = None
for e in self.exprs:
try:
loc, ret = e._parse(string, loc, doActions)
return loc, ParseResults(self, [ret])
except ParseException as err:
if err.loc > maxExcLoc:
maxException = err
maxExcLoc = err.loc
except IndexError:
if len(string) > maxExcLoc:
maxException = ParseException(string, len(string), self)
maxExcLoc = len(string)
# only got here if no expression matched, raise exception for match that made it the furthest
else:
if maxException is not None:
maxException.msg = "Expecting " + text(self)
raise maxException
else:
raise ParseException(self, loc, string)
