Comment by jbm | Hacker News Reader

Comment by jbm | Hacker News Reader

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For what it's worth, I used variable variables when making a DB class for a project I was working on last year.

It isn't something you can easily debug and it is complicated. That said, it isn't the gates to hell that it is represented as. It's a tool, and it can make code cleaner if you want it to.

function __tostring(){ $items = ['title','header','comment'] foreach($items as $item){ echo $this->$item; } }

Make that list of class variables much longer and you start to see the benefits in certain cases.

There are times when I do miss variable variables.

Python has it in a more object-oriented way ...

    def print_string(self):
        items = ['title', 'header', 'comment']
        for item in items:
            print getattr(self, item)

Where "getattr" is just a pretty protocol for calling ...

    self.__dict__[item]

This extends to whatever you want, including members of namespaces (like declared classes, functions, other namespaces, etc...)

There is actually a little more to getattr in that __dict__ just has attributes local to that instance where as getattr (also instance.attribute syntax) also accesses class attributes, non-bound methods, and properties. Additionally, these non-local attributes can also be inherited from parent classes.

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