linkchecker/PyLR/tests/MathParser.py

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"""
tests/MathParser.py -- created Mon Feb 28 00:06:56 2000
This file was automatically generated by the PyLR parser generator.
It defines the tables 'actiontable', 'gototable', and 'prodinfo'. These
tables are used to give functionality to a parsing engine. It also defines
A Parser class called MathParser which will use this engine. It's usage
is indicated in MathParser's doc-string.
"""
#
# this section contains source code added by the user
# plus 'import PyLR'
#
import MathLexer
import PyLR
#
# the action table means
# ('s', -1) shift
# ('r', <n>) reduce with production n
# ('a', -1) accept
# ('', -1) error
# each row represents a state and each column a terminal lookahead symbol
# Lexer symbols are:
# ['EOF', 'INT', 'PLUS', 'TIMES', 'LPAR', 'RPAR']
#
_actiontable = [
[('', -1), ('s', 4), ('', -1), ('', -1), ('s', 5), ('', -1)],
[('a', -1), ('', -1), ('s', 6), ('', -1), ('', -1), ('', -1)],
[('r', 2), ('', -1), ('r', 2), ('s', 7), ('', -1), ('r', 2)],
[('r', 4), ('', -1), ('r', 4), ('r', 4), ('', -1), ('r', 4)],
[('r', 6), ('', -1), ('r', 6), ('r', 6), ('', -1), ('r', 6)],
[('', -1), ('s', 4), ('', -1), ('', -1), ('s', 5), ('', -1)],
[('', -1), ('s', 4), ('', -1), ('', -1), ('s', 5), ('', -1)],
[('', -1), ('s', 4), ('', -1), ('', -1), ('s', 5), ('', -1)],
[('', -1), ('', -1), ('s', 6), ('', -1), ('', -1), ('s', 11)],
[('r', 1), ('', -1), ('r', 1), ('s', 7), ('', -1), ('r', 1)],
[('r', 3), ('', -1), ('r', 3), ('r', 3), ('', -1), ('r', 3)],
[('r', 5), ('', -1), ('r', 5), ('r', 5), ('', -1), ('r', 5)]
]
#
# the goto table, each row represents a state
# and each column the nonterminal that was on the lhs of the
# reduction
#
_gototable = [
[1, 1, 2, 2, 3, 3],
[None, None, None, None, None, None],
[None, None, None, None, None, None],
[None, None, None, None, None, None],
[None, None, None, None, None, None],
[8, 8, 2, 2, 3, 3],
[None, None, 9, 9, 3, 3],
[None, None, None, None, 10, 10],
[None, None, None, None, None, None],
[None, None, None, None, None, None],
[None, None, None, None, None, None],
[None, None, None, None, None, None]
]
#
# This is the prodinfo table. each row represents a production
# the entries are the length of the production, the name of a method
# in an instance of the MathParser class below that gets called
# when that production occurs, and the index of the lhs in the
# nonterminals (as in the gototable)
#
_prodinfo = [
(3, 'addfunc', 0), # expression: expression 2 term (addfunc)
(1, 'unspecified', 0), # expression: term (unspecified)
(3, 'timesfunc', 2), # term: term 3 factor (timesfunc)
(1, 'unspecified', 2), # term: factor (unspecified)
(3, 'parenfunc', 4), # factor: 4 expression 5 (parenfunc)
(1, 'unspecified', 4), # factor: 1 (unspecified)
]
class MathParser(PyLR.Parser):
"""
this class was produced automatically by the PyLR parser generator.
It is meant to be subclassed to produce a parser for the grammar
expression: expression PLUS term (addfunc);
expression: term (unspecified);
term: term TIMES factor (timesfunc);
term: factor (unspecified);
factor: LPAR expression RPAR (parenfunc);
factor: INT (unspecified);
While parsing input, if one of the above productions is recognized,
a method of your sub-class (whose name is indicated in parens to the
right) will be invoked. Names marked 'unspecified' should be ignored.
usage:
class MyMathParser(MathParser):
# ...define the methods for the productions...
p = MyMathParser(); p.parse(text)
"""
def __init__(self):
lexer = MathLexer.MathLexer()
PyLR.Parser.__init__(self, lexer, _actiontable, _gototable, _prodinfo)