expr.py 文件源码

def compare(self):
        left = Expr.parse_value_expr(self.expr.left, self.context)
        right = Expr.parse_value_expr(self.expr.comparators[0], self.context)
        if isinstance(self.expr.ops[0], ast.In) and \
           isinstance(right.typ, ListType):
            if not are_units_compatible(left.typ, right.typ.subtype) and not are_units_compatible(right.typ.subtype, left.typ):
                raise TypeMismatchException("Can't use IN comparison with different types!", self.expr)
            return self.build_in_comparator()
        else:
            if not are_units_compatible(left.typ, right.typ) and not are_units_compatible(right.typ, left.typ):
                raise TypeMismatchException("Can't compare values with different units!", self.expr)
        if len(self.expr.ops) != 1:
            raise StructureException("Cannot have a comparison with more than two elements", self.expr)
        if isinstance(self.expr.ops[0], ast.Gt):
            op = 'sgt'
        elif isinstance(self.expr.ops[0], ast.GtE):
            op = 'sge'
        elif isinstance(self.expr.ops[0], ast.LtE):
            op = 'sle'
        elif isinstance(self.expr.ops[0], ast.Lt):
            op = 'slt'
        elif isinstance(self.expr.ops[0], ast.Eq):
            op = 'eq'
        elif isinstance(self.expr.ops[0], ast.NotEq):
            op = 'ne'
        else:
            raise Exception("Unsupported comparison operator")
        if not is_numeric_type(left.typ) or not is_numeric_type(right.typ):
            if op not in ('eq', 'ne'):
                raise TypeMismatchException("Invalid type for comparison op", self.expr)
        ltyp, rtyp = left.typ.typ, right.typ.typ
        if ltyp == rtyp:
            return LLLnode.from_list([op, left, right], typ='bool', pos=getpos(self.expr))
        elif ltyp == 'decimal' and rtyp == 'num':
            return LLLnode.from_list([op, left, ['mul', right, DECIMAL_DIVISOR]], typ='bool', pos=getpos(self.expr))
        elif ltyp == 'num' and rtyp == 'decimal':
            return LLLnode.from_list([op, ['mul', left, DECIMAL_DIVISOR], right], typ='bool', pos=getpos(self.expr))
        else:
            raise TypeMismatchException("Unsupported types for comparison: %r %r" % (ltyp, rtyp), self.expr)