def leaveWhitespace( self ):
        self.skipWhitespace = False
        self.exprs = [ e.copy() for e in self.exprs ]
        for e in self.exprs:
            e.leaveWhitespace()
        return self
Extends leaveWhitespace defined in base class, and also invokes leaveWhitespace on
dataset/ETHPy150Open ipython/ipython-py3k/IPython/external/pyparsing/_pyparsing.py/ParseExpression.leaveWhitespace