(self, start=None)
Prepare for parsing.

        This *must* be called before starting to parse.

        The optional argument is an alternative start symbol; it
        defaults to the grammar's start symbol.

        You can use a Parser instance to parse any number of programs;
        each time you call setup() the parser is reset to an initial
        state determined by the (implicit or explicit) start symbol.
Prepare for parsing.
Prepare for parsing .
def setup(self, start=None):
        """Prepare for parsing.

        This *must* be called before starting to parse.

        The optional argument is an alternative start symbol; it
        defaults to the grammar's start symbol.

        You can use a Parser instance to parse any number of programs;
        each time you call setup() the parser is reset to an initial
        state determined by the (implicit or explicit) start symbol.

        """
        if start is None:
            start = self.grammar.start
        # Each stack entry is a tuple: (dfa, state, node).
        # A node is a tuple: (type, value, context, children),
        # where children is a list of nodes or None, and context may be None.
        newnode = (start, None, None, [])
        stackentry = (self.grammar.dfas[start], 0, newnode)
        self.stack = [stackentry]
        self.rootnode = None
        self.used_names = set()
def setup ( self , start = None ) : if start is None : start = self . grammar . start # Each stack entry is a tuple: (dfa, state, node). # A node is a tuple: (type, value, context, children), # where children is a list of nodes or None, and context may be None. newnode = ( start , None , None , [ ] ) stackentry = ( self . grammar . dfas [ start ] , 0 , newnode ) self . stack = [ stackentry ] self . rootnode = None self . used_names = set ( )