A matter of inout

[bearophile]

Artur Skawina:

> 'inout' basically means 'local const' - if you'd allow inout
> data to be modified then it wouldn't be possible to call the
> function with a const or immutable argument - which is the
> whole point of inout...
> You probably want 'inout(T)[]' if you're going to alter the
> array.

Using inout(T)[] gives the same error:

import std.stdio;
inout(T)[] forwardDifference(T)(inout(T)[] s, in int n) pure {
     foreach (_; 0 .. n)
         s[] -= s[1 .. $];
     return s[0 .. $ - n];
}
void main() {
     immutable A = [90.5, 47, 58, 29, 22, 32, 55, 5, 55, 73.5];
     foreach (level; 0 .. A.length)
         writeln(forwardDifference(A.dup, level));
}


Bye,
bearophile