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by pjmlp 1009 days ago
Except C is quite a poor example for how to use modules.

TU with opaque pointers can be used for such purposes, and they are, but still fail short of Modula-2, Mesa, CLU and UCSD Pascal, to cite contemporary examples.
1 comments
rewmie 1008 days ago
> Except C is quite a poor example for how to use modules.

How come? C makes it trivial to create self-contained modules.

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pjmlp 1008 days ago
C makes it trivial to create poor man's modules.

It lacks almost everything that a programming language with modules offers on its type system, and compiler toolchain.

Proper public/private types, module initialization/shutdown, linking with type checking, namespaces.

One can fake modules with void pointers, static types on translation units, prefixes that hopefully no one else is using, and that is about it.

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rewmie 1008 days ago
> Proper public/private types,

Modules either have types as part of their interface, or haven't. I C, the declarations shipped in the interface header represent the interface, and the types declared in it are public types.

C also supports symbols with internal linkage.

What exactly is missing?

> module initialization/shutdown,

What's wrong with initializing objects? Languages such as Rust also rely on factory methods to instantiate objects.

> linking with type checking,

The interface headers define the symbols, which must correspond to the symbols handled by the linker. What's missing?

> namespaces.

That definitely C doesn't support as a first class citizen, but this is nothing that symbol prefixes don't handle.

What's missing, then?

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