why no implicit convertion?

Tomek Sowiński just at ask.me
Wed Nov 17 13:32:21 PST 2010

Matthias Pleh <sufu at alter.com> napisał(a):

> void foo(char[] a) {}
> void bar(char[][] b) {}
> int main(string[] args)
> {
>      char[4] a;
>      char[4][4] b;
>      foo(a);        // OK: implicit convertion
>      bar(b);        // Error: cannot implicitly convert
>                     //        char[4u][4u] to char[][]
> }
> what is the reason for the different behaviour?

I *think* it's because multi-dim static arrays are a strip of contiguous  
memory and no length information is held with the data, so if it was  
converted to a dynamic array of arrays (who do hold their lengths), there  
wouldn't be room for the lengths of the arrays.

> What's best to pass such multidimensional arrays?

Good question. Maybe new char[][](4) and point the inner arrays to the  
chunks of the static array?


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