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0 pointsmgaunard2y ago0 comments

They're straightforward and easy to reason about.

Textual inclusion also allows a number of things modules do not.

The main disadvantage that they have, that they're stateful, is also true of module systems in many languages (e.g. python).

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dagmx2y ago

I greatly disagree with “easier to reason about”

Maybe in a clean, smaller codebase with minimal dependencies.

But the textual inclusion means that including one header can suddenly break previously compiling code. Unless that header is completely inclusive, that can mean a while of chasing down transitive headers till you find the problematic one.

mgaunardOP2y ago

The semantics are literally "it's the same as copy-pasting it where it's used". It doesn't get simpler than this.

There are much more things going on in the module system that you'd have to know about if you care about what's actually going on.

dagmx2y ago

The module system doesn’t have side effects on inclusion, whereas headers do.

So again, maybe if you have a smaller, cleaner or dependency free codebase, then it’s not an issue.

But in any codebase of major scale or legacy, headers can introduce several issues that aren’t possible with the module interface.

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maccard2y ago

You're really burying the lede here.

Headers are literal copy paste, and are entirely different. Anyone who has ever had to define WIN32_LEAN_AND_MEAN knows that there's _way_ more going on here.

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dagmx2y ago

I greatly disagree with “easier to reason about”

Maybe in a clean, smaller codebase with minimal dependencies.

mgaunardOP2y ago

The semantics are literally "it's the same as copy-pasting it where it's used". It doesn't get simpler than this.

There are much more things going on in the module system that you'd have to know about if you care about what's actually going on.

dagmx2y ago

The module system doesn’t have side effects on inclusion, whereas headers do.

So again, maybe if you have a smaller, cleaner or dependency free codebase, then it’s not an issue.

But in any codebase of major scale or legacy, headers can introduce several issues that aren’t possible with the module interface.

1 more reply

maccard2y ago

You're really burying the lede here.

Headers are literal copy paste, and are entirely different. Anyone who has ever had to define WIN32_LEAN_AND_MEAN knows that there's _way_ more going on here.

1 more reply

j / k navigate · click thread line to collapse