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Comment by daghamm | Hacker News Reader

C type declarations are quite sane, until you need function pointers. Then things get really crazy.

Consider this type declaration in Go:

    func(string) []func(int)[]*float64

This took me 5 seconds to write. The C/C++ counterpart would probably take an hour to get right :(

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Function pointers are easy if you typedef the function type.

What a pointer to function (int) returning int?

The difficult way:

    int (*p)(int);

The easy way:

    typedef int Func(int);
    Func *p;

The typedef reads just like a normal function declaration except for the name is the type name rather than the function symbol name. Just like a function declaration, you can add more documentation by giving the parameters names. e.g.:

    // used for some hypothetical allocator API
    typedef void *Alloc(size_t size);

Similar trick can be used for pointers to arrays (just typedef the array type). Although in practice pointers to arrays just make for awful code.

Hmm... Let's see...

Oh, functions can't return arrays in C. That would be a pointer. Well, that makes it easier.

    double **(**(*)(char *))(int)

It did take a couple minutes, but I just woke up. Also, idiomatically there would be a typedef:

    typedef double **A(int);
    typedef A **B(char *);
    B *

That took a few seconds to write.

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