diff --git a/arpeggio/__init__.py b/arpeggio/__init__.py
index df08c4e5f59e886708758ec3186f4e50281445e2..732fb4daf264a3496d64d670cd554bb2f286bd07 100644
--- a/arpeggio/__init__.py
+++ b/arpeggio/__init__.py
@@ -1,15 +1,15 @@
# -*- coding: utf-8 -*-
-################################################################################
+###############################################################################
# Name: arpeggio.py
# Purpose: PEG parser interpreter
# Author: Igor R. Dejanović <igor DOT dejanovic AT gmail DOT com>
# Copyright: (c) 2009 Igor R. Dejanović <igor DOT dejanovic AT gmail DOT com>
# License: MIT License
#
-# This is an implementation of packrat parser interpreter based on PEG grammars.
-# Grammars are defined using Python language constructs or the PEG textual
-# notation.
-################################################################################
+# This is an implementation of packrat parser interpreter based on PEG
+# grammars. Grammars are defined using Python language constructs or the PEG
+# textual notation.
+###############################################################################
from __future__ import print_function, unicode_literals
import re
@@ -51,7 +51,8 @@ class NoMatch(Exception):
Args:
value (str): A name of the parsing expression or rule.
- position (int): A position in the input stream where exception occurred.
+ position (int): A position in the input stream where exception
+ occurred.
parser (Parser): An instance of a parser.
"""
def __init__(self, rule, position, parser):
@@ -177,7 +178,8 @@ class ParsingExpression(object):
result, new_pos = self.result_cache[c_pos]
parser.position = new_pos
if parser.debug:
- print("** Cache hit for [{}, {}] = '{}'".format(self.name, c_pos, str(result)))
+ print("** Cache hit for [{}, {}] = '{}'"
+ .format(self.name, c_pos, str(result)))
if parser.debug:
print("<< Leaving rule {}".format(self.name))
return result
@@ -429,12 +431,12 @@ class Match(ParsingExpression):
@property
def name(self):
return "%s(%s)" % (self.__class__.__name__, self.to_match)
-
+
def parse(self, parser):
self._parse_intro(parser)
if parser._in_parse_comment:
return self._parse(parser)
-
+
c_pos = parser.position
comments = []
@@ -472,8 +474,8 @@ class RegExMatch(Match):
This Match class will perform input matching based on Regular Expressions.
Args:
- to_match (regex string): A regular expression string to match. It will be
- used to create regular expression using re.compile.
+ to_match (regex string): A regular expression string to match.
+ It will be used to create regular expression using re.compile.
'''
def __init__(self, to_match, rule=None, flags=None):
super(RegExMatch, self).__init__(rule)
@@ -529,10 +531,10 @@ class StrMatch(Match):
def __eq__(self, other):
return self.to_match == str(other)
-
+
def __hash__(self):
return hash(self.to_match)
-
+
# HACK: Kwd class is a bit hackish. Need to find a better way to
# introduce different classes of string tokens.
@@ -568,7 +570,8 @@ class EndOfFile(Match):
parser._nm_raise(self.name, c_pos, parser)
-def EOF(): return EndOfFile()
+def EOF():
+ return EndOfFile()
# ---------------------------------------------------------
@@ -584,8 +587,10 @@ class ParseTreeNode(object):
Attributes:
rule (str): The name of the rule that created this node or empty
string in case this node is created by a non-root pexpression.
- position (int): A position in the input stream where the match occurred.
- error (bool): Is this a false parse tree node created during error recovery.
+ position (int): A position in the input stream where the match
+ occurred.
+ error (bool): Is this a false parse tree node created during error
+ recovery.
comments : A parse tree of comment(s) attached to this node.
"""
def __init__(self, rule, position, error):
@@ -698,7 +703,8 @@ class SemanticAction(object):
def first_pass(self, parser, node, nodes):
"""
Called in the first pass of tree walk.
- This is the default implementation used if no semantic action is defined.
+ This is the default implementation used if no semantic action is
+ defined.
"""
# Special case. If only one child exist return it.
if len(nodes)==1:
@@ -720,7 +726,7 @@ class SemanticAction(object):
else:
# Return the only non-string child
retval = last_non_str
-
+ # If there is only one non-string child return
return retval
@@ -740,7 +746,8 @@ class Parser(object):
debug (bool): If true debugging messages will be printed.
comments_model: parser model for comments.
"""
- def __init__(self, skipws=True, ws=DEFAULT_WS, reduce_tree=True, debug=False):
+ def __init__(self, skipws=True, ws=DEFAULT_WS, reduce_tree=True,
+ debug=False):
self.skipws = skipws
self.ws = ws
self.reduce_tree = reduce_tree
@@ -766,9 +773,9 @@ class Parser(object):
Creates Abstract Semantic Graph (ASG) from the parse tree.
Args:
- sem_actions (dict): The semantic actions dictionary to use for semantic
- analysis. Rule names are the keys and semantic action objects are
- values.
+ sem_actions (dict): The semantic actions dictionary to use for
+ semantic analysis. Rule names are the keys and semantic action
+ objects are values.
"""
if not self.parse_tree:
raise Exception("Parse tree is empty. You did call parse(), didn't you?")
@@ -791,20 +798,23 @@ class Parser(object):
called in the second pass.
"""
if self.debug:
- print("Walking down ", node.name, " type:", type(node), "str:", str(node))
+ print("Walking down ", node.name, " type:",
+ type(node), "str:", str(node))
children = []
if isinstance(node, NonTerminal):
for n in node:
children.append(tree_walk(n))
if self.debug:
- print("Visiting ", node.name, "= '", str(node), "' type:", type(node), \
+ print("Visiting ", node.name, "= '", str(node),
+ "' type:", type(node), \
"len:", len(node) if isinstance(node, list) else "")
for i, a in enumerate(children):
- print ("\t%d:"%(i+1), str(a), "type:", type(a))
+ print ("\t%d:" % (i + 1), str(a), "type:", type(a))
if node.rule in sem_actions:
- retval = sem_actions[node.rule].first_pass(self, node, children)
+ retval = sem_actions[node.rule].first_pass(self,
+ node, children)
if hasattr(sem_actions[node.rule], "second_pass"):
for_second_pass.append((node.rule, retval))
else:
@@ -857,14 +867,14 @@ class Parser(object):
if self.input[self.line_ends[line - 1]] in '\n\r':
col -= 1
return line + 1, col + 1
-
+
def context(self, length=None, position=None):
"""
Returns current context substring, i.e. the substring around current
position.
Args:
- length(int): If given used to mark with asterisk a length chars from
- current position.
+ length(int): If given used to mark with asterisk a length chars
+ from the current position.
position(int): The position in the input stream.
"""
if not position:
@@ -873,7 +883,7 @@ class Parser(object):
return "{}*{}*{}".format(
str(self.input[max(position - 10, 0):position]),
str(self.input[position:position + length]),
- str(self.input[position + length:position+10]))
+ str(self.input[position + length:position + 10]))
else:
return "{}*{}".format(
str(self.input[max(position - 10, 0):position]),
@@ -960,7 +970,8 @@ class ParserPython(Parser):
if isinstance(c_rule, CrossRef):
self.__cross_refs += 1
if self.debug:
- print("CrossRef usage: {}".format(c_rule.rule_name))
+ print("CrossRef usage: {}"
+ .format(c_rule.rule_name))
return c_rule
# Semantic action for the rule
@@ -977,8 +988,8 @@ class ParserPython(Parser):
# Update cache
__rule_cache[rule] = retval
if self.debug:
- print("New rule: {} -> {}".format(rule,
- retval.__class__.__name__))
+ print("New rule: {} -> {}"
+ .format(rule, retval.__class__.__name__))
elif isinstance(expression, Match):
retval = expression