eval() function changes

[jack_norton]

OK it's me again
I thought it was my bad coding in Roommates to cause the problems, but I found even in SOTW or other program I still have this issue with eval. In practice, what before was working fine, in the latest Ren'Py crashes. A line like:

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rv = eval(self.item["Superclass"])(self.item["Name"], self.item["ID"], self.item["Type"],tmp_values,tmp_keys,self.item["D-Type"],eval(self.item["Price"]),eval(self.item["Dropable"]),eval(self.item["Unique"]),self.item["Icon"],self.item["Description"],self.level)

was working completely fine, and now instead returns the error:
TypeError: eval() arg 1 must be a string or code object

So I'm wondering why? I mean, if worked fine in the past 4 years (or so since I've been using Ren'Py) why suddenly breaks now ? some changes introduced by newer version of Python? How can I fix this (except for not upgrading)? Thanks

[Counter Arts]

Have you thought of throwing around function pointers instead?

[jack_norton]

Well, I can do any "workaround" of course. The problem is when something that used to work for years suddenly changes, so I have to search in the code and find a solution for all those cases, and then retest the game to make sure it works as intended. I am thinking to code a "replacement function".
But of course it's not an ideal solution, so I was wondering if I'm missing something, if is a Ren'Py bug, or if there's an easier fix before changing my code in 60+ different places

[jack_norton]

Haha in the end the solution was super simple:

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    def evalFixed(expression):
        expressionFixed = str(expression)

[jack_norton]

Haha in the end the solution was super simple:

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    def evalFixed(expression):
        expressionFixed = str(expression)
        return eval(expressionFixed)

[PyTom]

It would probably be better to do something line:

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def evalFixed(expression):
    if not isinstance(expression, basestring):
        expression = repr(expression)

    return eval(expression)

What's weird is that this should never have worked - eval has always been defined to take a string or code object. I haven't changed it recently, and it was only ever documented as part of Python, where it's defined as:

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eval(...)
    eval(source[, globals[, locals]]) -> value
    
    Evaluate the source in the context of globals and locals.
    The source may be a string representing a Python expression
    or a code object as returned by compile().
    The globals must be a dictionary and locals can be any mapping,
    defaulting to the current globals and locals.
    If only globals is given, locals defaults to it.

In general, eval is a bad idea. It has to compile, transform, and execute python code, which is a slow process. This might be part of the reason why Roomates has been having performance problems on mobile.

[jack_norton]

Ah OK, but in Roommates the eval is not used a lot honestly
But yeah I'll try to use it less in future games! thanks