Function guarded_eval

IPython/core/guarded_eval.py:433–466

Evaluate provided code in the evaluation context. If evaluation policy given by context is set to ``forbidden`` no evaluation will be performed; if it is set to ``dangerous`` standard :func:`eval` will be used; finally, for any other, policy :func:`eval_node` will be called on parse

(code: str, context: EvaluationContext)

def guarded_eval(code: str, context: EvaluationContext):
    """Evaluate provided code in the evaluation context.

    If evaluation policy given by context is set to ``forbidden``
    no evaluation will be performed; if it is set to ``dangerous``
    standard :func:`eval` will be used; finally, for any other,
    policy :func:`eval_node` will be called on parsed AST.
    """
    locals_ = context.locals

    if context.evaluation == "forbidden":
        raise GuardRejection("Forbidden mode")

    # note: not using `ast.literal_eval` as it does not implement
    # getitem at all, for example it fails on simple `[0][1]`

    if context.in_subscript:
        # syntactic sugar for ellipsis (:) is only available in subscripts
        # so we need to trick the ast parser into thinking that we have
        # a subscript, but we need to be able to later recognise that we did
        # it so we can ignore the actual __getitem__ operation
        if not code:
            return tuple()
        locals_ = locals_.copy()
        locals_[SUBSCRIPT_MARKER] = IDENTITY_SUBSCRIPT
        code = SUBSCRIPT_MARKER + "[" + code + "]"
        context = context.replace(locals=locals_)

    if context.evaluation == "dangerous":
        return eval(code, context.globals, context.locals)

    node = ast.parse(code, mode="exec")

    return eval_node(node, context)


BINARY_OP_DUNDERS: dict[type[ast.operator], tuple[str]] = {