What's the name of a pre-compilation 'variable' constant in C?

Question

It's a long time since I did any coding of any sort.

I'm trying to remember the name (in C) of an item you put at the beginning of your code that allows compilation to a constant for efficiency but can have its value adjusted before compilation if necessary.

What is it called? (specifically the name in C and optionally the name in general)

Thanks.

You mean a macro? And if that's what you mean, those don't exist in Java. — Blaze, Nov 29 '18 at 10:45
@Antti Haapala - Okay but my real question was "is *this thing* available in Java and/or JavaScript". I needed to know the name before I could ask. It seemed wasteful to ask lots of different questions but I see your point. — chasly - supports Monica, Nov 29 '18 at 10:57
@chaslyfromUK because there are answers for **everything**. For example: https://stackoverflow.com/questions/1927107/define-in-java . There are no answers to the question "can you help me", because [it is not an actual question](https://meta.stackoverflow.com/questions/284236/why-is-can-someone-help-me-not-an-actual-question) — Antti Haapala -- Слава Україні, Nov 29 '18 at 10:58
The term you are looking for is _integer constant expressions_. They can be placed behind a `#define` or elsewhere in the code. For example in `int x = 5 + 7;`, the `5 + 7` is an integer constant expression and will be calculated at compile-time. The resulting machine code will look something like "load 12 into register". — Lundin, Nov 29 '18 at 11:39

score 2 · Accepted Answer · answered Nov 29 '18 at 10:49

2

#define statements allow you to define a constant at the beginning of your code.

answered Nov 29 '18 at 10:49

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What's the name of a pre-compilation 'variable' constant in C?

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