C callback receives bad pointer argument

[bearophile]

Marco Cosentino:

> Translated correctly the C callback style into D delegates types with alias.

D has function pointers too.


> Managed some segment faluts happened when not using toStringz() with 
> some "strings"

For this kind of bugs I suggest to use the D type system in a smarter way. With extern you allowed to give what type you want to the C char* arguments, so you are free to use another type. An example:


import std.stdio: writeln;
import std.string: toStringz;

typedef const char* ccharPtr;

// example of C function, with smarter string type
extern(C) size_t strlen(ccharPtr str);

ccharPtr toStringz2(string s) {
    return cast(ccharPtr)toStringz(s);
}

void main() {
    string s1 = "this is ";
    string s2 = s1 ~ "just a string";
    writeln(s2.length);
    auto cs = toStringz2(s2);
    writeln(strlen(cs));
}


Now that typedef is deprecated what solution do you suggest instead?

Bye,
bearophile