I’m working through the vulkan tutorial and came across GLFW_TRUE and GLFW_FALSE. I presume there’s a good reason but in looking at the docs it’s just defining 1 and 0, so I’m sorta at a loss as to why some libraries do this (especially in cpp?).

Tangentially related is having things like vk_result which is a struct that stores an enum full of integer codes.

Wouldn’t it be easier to replace these variables with raw int codes or in the case of GLFW just 1 and 0?

Coming mostly from C, and having my caps lock bound to escape for vim, the amount of all caps variables is arduous for my admittedly short fingers.

Anyway hopefully one of you knows why libraries do this thanks!

  •  floofloof   ( @floofloof@lemmy.ca ) 
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    1 month ago

    My boss insisted, before I arrived at the company, that everything in the database be coded so that 1 = Yes and 2 = No, because that’s the way he likes to think of it. It causes us daily pain.

  •  Azzu   ( @Azzu@lemm.ee ) 
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    331 month ago

    My brain is so used to seeing political content that I read “why do liberals define their own true and false” and was already like “what kind of shit take am I going to have fun reading today”

  • It’s because the Booleans sometimes are flipped in display-server technology from the 1980s, particularly anything with X11 lineage, and C didn’t have Boolean values back then. More generally, sometimes it’s useful to have truthhood be encoded low or 0, as in common Forths or many lower-level electrical-engineering protocols. The practice died off as popular languages started to have native Boolean values; today, about three quarters of new developers learn Python or ECMAScript as their first language, and FFI bindings are designed to paper over such low-level details. You’ll also sometimes see newer C/C++ libraries depending on newer standards which add native Booleans.

    As a fellow vim user with small hands, here are some tricks. The verb gU will uppercase letters but not underscores or hyphens, so sentences like gUiw can be used to uppercase an entire constant. The immediate action ~ which switches cases can be turned into a verb by :set tildeop, after which it can be used in a similar way to gU. If constants are all namespaced with a prefix followed by something unique like an underscore, then the prefix can be left out of new sections of code and added back in with a macro or a :%s replacement.

  • GLFW is a C library, not a C++ one, and an old one at that, and so the reason is that a long time ago, there was no bool in C. Every library would make their own true and false bc it’s handy to have.

    Nowadays, the type _Bool has been added to C, and C++ has built-in bool, but you can still see the legacy of no boolean in C as to use the type name “bool” as well as the key words “true” and “false” for 1 and 0, you have to include “stdbool.h,” as well as in custom types in these old GL-adjacent libraries.

  • I found the comments/answers about backwards compatibility of not defined booleans and negative true interesting and plausible.

    What I first thought of was that TRUE and FALSE can be redefined, so it serves as ensurance that within the library consistent values are being used no matter what other libs and callers do with their typing and definitions.