Python pyparsing.infixNotation() Examples

The following are 3 code examples of pyparsing.infixNotation(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module pyparsing , or try the search function .
Example #1
Source File: expression_parser.py    From rekall with GNU General Public License v2.0 6 votes vote down vote up 
def expression_parser(self):
        """A function returning a (pyparsing) parser for parsing C expressions.

        Returns:
            a (pyparsing) parser for parsing C expressions.
        """
        precedence = (self._build_precedence(_UNARY_MACROS) +
                      self._build_precedence(_PRECEDENCE))

        self.expression = pyparsing.Forward()

        # pylint: disable=expression-not-assigned
        self.expression << (
            pyparsing.infixNotation(
                baseExpr=self._base_or_array_expression(),
                opList=precedence,
            )
        )

        return self.expression
Example #2
Source File: stringparser.py    From bob with GNU General Public License v3.0 5 votes vote down vote up 
def __init__(self):
        # create parsing grammer
        sQStringLiteral = pyparsing.QuotedString("'")
        sQStringLiteral.setParseAction(
            lambda s, loc, toks: StringLiteral(s, loc, toks, False))

        dQStringLiteral = pyparsing.QuotedString('"', '\\')
        dQStringLiteral.setParseAction(
            lambda s, loc, toks: StringLiteral(s, loc, toks, True))

        stringLiteral = sQStringLiteral | dQStringLiteral

        functionCall = pyparsing.Forward()
        functionArg = stringLiteral | functionCall
        functionCall << pyparsing.Word(pyparsing.alphas, pyparsing.alphanums+'-') + \
            pyparsing.Suppress('(') + \
            pyparsing.Optional(functionArg +
                pyparsing.ZeroOrMore(pyparsing.Suppress(',') + functionArg)) + \
            pyparsing.Suppress(')')
        functionCall.setParseAction(
            lambda s, loc, toks: FunctionCall(s, loc, toks))

        predExpr = pyparsing.infixNotation(
            stringLiteral ^ functionCall ,
            [
                ('!',  1, pyparsing.opAssoc.RIGHT, lambda s, loc, toks: NotOperator(s, loc, toks)),
                ('<',  2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('<=', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('>',  2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('>=', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('==', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('!=', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryStrOperator)),
                ('&&', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryBoolOperator)),
                ('||', 2, pyparsing.opAssoc.LEFT,  infixBinaryOp(BinaryBoolOperator))
            ])

        self.__ifgrammer = predExpr
Example #3
Source File: expression.py    From monasca-analytics with Apache License 2.0 4 votes vote down vote up 
def __init__(self):
        """
        Create a parser that parse arithmetic expressions. They can
        contains variable identifiers or raw numbers. The meaning
        for the identifiers is left to the
        """
        number = p.Regex(r'\d+(\.\d*)?([eE]\d+)?')
        identifier = p.Word(p.alphas)
        terminal = identifier | number
        self._expr = p.infixNotation(terminal, [
            (p.oneOf('* /'), 2, p.opAssoc.LEFT),
            (p.oneOf('+ -'), 2, p.opAssoc.LEFT)
        ]) + p.stringEnd()