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Blog post where someone used Python quirks to evaluate false == true (lemmy.dbzer0.com)
submitted 1 year ago* (last edited 1 year ago) by CrackedLinuxISO@lemmy.dbzer0.com to c/programmer_humor@programming.dev
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Does anyone remember an old blog post where someone used various Python language hacks to override boolean primitives, such that the statement false == true evaluated as true? I'm 90% sure it was python, but maybe it was some other language.

I've been looking for that post recently, but haven't had any luck.

Thanks to antagonistic for finding it! I guess it was less of an "exploit", and more of a "please don't touch the loaded foot-gun"

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[-] Antagnostic@lemmy.world 22 points 1 year ago

This?

[-] solrize@lemmy.ml 12 points 1 year ago* (last edited 1 year ago)

The builtin names are True and False and they became keywords a while back. true and false are just ordinary variables that you can set to whatever you want.

Meanwhile, in Forth:

: 2 3 ; \ define 2 as 3
2 2 + .  6 ok   \ shows that 2+2 is now 6
[-] undefined@lemmy.hogru.ch 3 points 1 year ago

God I hated that about Python. Why tf we capitalizing True and False?

[-] lime@feddit.nu 4 points 1 year ago

all builtin constants are capitalised.

[-] RecallMadness@lemmy.nz 4 points 1 year ago* (last edited 1 year ago)

All… five of them!

The other 7 are all lowercase. (One of you ignore site)

[-] lime@feddit.nu 2 points 1 year ago

yeah but dunders usually aren't included in counts

[-] squaresinger@lemmy.world 1 points 1 year ago

And they also don't follow the conventions for constants otherwise, which are all caps.

[-] lime@feddit.nu 1 points 1 year ago

i think we're talking about different things.

[-] solrize@lemmy.ml 2 points 1 year ago

They are constants, like None, which has always been around.

[-] ExperimentalGuy@programming.dev 8 points 1 year ago

I feel like you hear fuckery like that more in JavaScript.

[-] who@feddit.org 4 points 1 year ago* (last edited 1 year ago)

Python doesn't have true or false keywords, nor any other primitives by those names.

So either you're thinking of a different language, or different identifiers, or someone assigned equal values to variables with those names and then blogged about it.

[-] Antagnostic@lemmy.world 4 points 1 year ago

This changed in 3.0 to my knowledge. Ref: https://wiki.python.org/moin/Python3.0#f

[-] who@feddit.org 4 points 1 year ago* (last edited 1 year ago)

That change is about True and False, not true and false. If OP was thinking of the former pair, it would seem my "different identifiers" guess was correct.

[-] LodeMike@lemmy.today 3 points 1 year ago

Maybe they did "False is True" because they're both the same Python object?

[-] solrize@lemmy.ml 5 points 1 year ago

I just checked and they aren't.

[-] LodeMike@lemmy.today 3 points 1 year ago* (last edited 1 year ago)

Maybe they defined them as variable names instead?

Or they could have just changed the language. Do you remember them compiling or editing C? (Python is usually run on cpython)

[-] solrize@lemmy.ml 5 points 1 year ago

True is False gives false in Python 2.7.18 as well as 3.x. But, in 2.x, they aren't keywords, so you can say True=False=5 and then they are both the same object.

[-] LodeMike@lemmy.today 3 points 1 year ago

I really need to stop trusting how durable this language is.

this post was submitted on 15 Aug 2025
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