On Sunday, 2 August 2015 at 08:08:05 UTC, tcak wrote:
[code]
void func1(N)( const N name )
if( is(N: string) || is(N: char[]) )
{
func2( name );
}
void func2(N)( const N name )
if( is(N: string) || is(N: char[]) )
{}
void main(){
char[] blah = ['b', 'l', 'a', 'h'];
func1( blah );
//func1( "blah" ); // this works
}
[/code]
[result]
test.d(4): Error: template test.func2 cannot deduce function
from argument types !()(const(char[])), candidates are:
test.d(7): test.func2(N)(const N name) if (is(N :
string) || is(N : char[]))
[/result]
When func1 is called with blah variable, I assume that N is
char[].
Yup.
From there, when func2 is called by func1, name should be
const(char[]).
Yup.
But since func2 defined name parameter with const, shouldn't
the compiler accept const part of const(char[]) as func2's
const, and accept N as char[] still?
Nope. When removing the top level const of `const(char[])`, it
becomes `const(char)[]`. Test for that in your template
constraint and it works.