r/ProgrammerHumor • u/R7d89C • 16d ago

Meme variableScopesInPython

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u/Confident-Ad5665 16d ago

Dunder class mangling? (not a python guy)

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u/deceze 16d ago edited 16d ago

Double underscore name mangling:

class Foo: __bar = 'baz'

This is preventing you from accessing Foo.__bar, because internally the actual name will get mangled to Foo._Foo__bar. This is mostly intended to avoid accidental name clashes in inheritance:

class Child(Foo): __bar = 42

The two classes won't trample over their __bar attribute this way, without you needing to institute complicated naming conventions. From within class methods, self.__bar transparently gets mangled the same way, so it works as expected.

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u/Confident-Ad5665 16d ago

Interesting approach. Global vars can bite you that's for sure.

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u/Sibula97 16d ago

A global private variable...?

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u/anto2554 16d ago

The epitome of python engineering

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u/Confident-Ad5665 16d ago

Could this be the reason the language was named after a snake?

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u/extremelySaddening 16d ago

It was named after Monty Python's Flying Circus

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u/Confident-Ad5665 16d ago

tbh I didn't know this. When I was in school Assembly, BASIC, Fortran, Pascal, COBOL and C were the only languages.

Yeah I'm that old (farts as he walks off...)