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December 05, 2012
Appending immutable char implicit cast to int, bug or feature?
This is simple code to create all genetic combinations from two 
organisms.

string[] mixGenes(string a, string b) {
	string[] result;

	foreach(i;0..2)
		foreach(j;0..2)
			foreach(k;2..4)
				foreach(m;2..4)
					result ~= [a[i]] ~ [b[j]] ~ [a[k]] ~ [b[m]];

	return result;
}

This works, however when I remove the brackets:

result ~= a[i] ~ b[j] ~ a[k] ~ b[m];

I get the error:

Error: incompatible types for ((cast(int)a[cast(uint)i]) ~ 
(cast(int)b[cast(uint)j])): 'int' and 'int'

Why, when trying to append immutable chars to make a string, has 
it decided to implicitly cast them to int?
December 06, 2012
Re: Appending immutable char implicit cast to int, bug or feature?
On 12/05/2012 09:30 AM, ixid wrote:
> This is simple code to create all genetic combinations from two organisms.
>
> string[] mixGenes(string a, string b) {
> string[] result;
>
> foreach(i;0..2)
> foreach(j;0..2)
> foreach(k;2..4)
> foreach(m;2..4)
> result ~= [a[i]] ~ [b[j]] ~ [a[k]] ~ [b[m]];
>
> return result;
> }
>
> This works, however when I remove the brackets:
>
> result ~= a[i] ~ b[j] ~ a[k] ~ b[m];
>
> I get the error:
>
> Error: incompatible types for ((cast(int)a[cast(uint)i]) ~
> (cast(int)b[cast(uint)j])): 'int' and 'int'
>
> Why, when trying to append immutable chars to make a string, has it
> decided to implicitly cast them to int?

I don't know where that cast occurs but I wanted to state the obvious: 
Operator ~ is defined only for arrays.

Ali
December 06, 2012
Re: Appending immutable char implicit cast to int, bug or feature?
> I don't know where that cast occurs but I wanted to state the 
> obvious: Operator ~ is defined only for arrays.

Would having it also work for individual units to make an array 
be a plausible enhancement request? It would seem like a natural 
use of the operator.
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