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digitalmars.D.learn - itfi limitation or bug on my part?

reply Brad Roberts <braddr puremagic.com> writes:
module test;

void main()
{
    int[] foos;
    func1(foos);
}

void func1(T)(const T[] foos)
{
    T afoo;
    func2(foos, afoo);
}

void func2(T)(const T[] foos, out T afoo)
{
}

$ dmd -c test.d
test.d(12): Error: template test.func2(T) does not match any function template
declaration
test.d(12): Error: template test.func2(T) cannot deduce template function from
argument types !()(const(int[]),int)
test.d(6): Error: template instance test.func1!(int) error instantiating

Ignore style.. this is a massively reduced case from a much more complex block
of code.
Aug 07 2010
parent reply Don <nospam nospam.com> writes:
Brad Roberts wrote:
 module test;
 
 void main()
 {
     int[] foos;
     func1(foos);
 }
 
 void func1(T)(const T[] foos)
 {
     T afoo;
     func2(foos, afoo);
 }
 
 void func2(T)(const T[] foos, out T afoo)
 {
 }
 
 $ dmd -c test.d
 test.d(12): Error: template test.func2(T) does not match any function template
 declaration
 test.d(12): Error: template test.func2(T) cannot deduce template function from
 argument types !()(const(int[]),int)
 test.d(6): Error: template instance test.func1!(int) error instantiating
 
 Ignore style.. this is a massively reduced case from a much more complex block
 of code.
 
Looks like a compiler bug. If you change func2 to this: void func2(T, U)(const T[] foos, out U afoo) { static assert(is(T==U)); } test0.d(212): Error: static assert (is(const(int) == int)) is false test0.d(207): instantiated from here: func2!(const(int),int) test0.d(201): instantiated from here: func1!(int) T should be "const(int)" instead of "int".
Aug 07 2010
parent Brad Roberts <braddr puremagic.com> writes:
On 8/7/2010 12:42 PM, Don wrote:
 Brad Roberts wrote:
 module test;

 void main()
 {
     int[] foos;
     func1(foos);
 }

 void func1(T)(const T[] foos)
 {
     T afoo;
     func2(foos, afoo);
 }

 void func2(T)(const T[] foos, out T afoo)
 {
 }

 $ dmd -c test.d
 test.d(12): Error: template test.func2(T) does not match any function template
 declaration
 test.d(12): Error: template test.func2(T) cannot deduce template function from
 argument types !()(const(int[]),int)
 test.d(6): Error: template instance test.func1!(int) error instantiating

 Ignore style.. this is a massively reduced case from a much more complex block
 of code.
Looks like a compiler bug. If you change func2 to this: void func2(T, U)(const T[] foos, out U afoo) { static assert(is(T==U)); } test0.d(212): Error: static assert (is(const(int) == int)) is false test0.d(207): instantiated from here: func2!(const(int),int) test0.d(201): instantiated from here: func1!(int) T should be "const(int)" instead of "int".
Other way around.. T should be 'int' instead of 'const(int)'. Thanks for the confirmation. I thought the same thing but wanted independent confirmation. I'll file the bug.
Aug 07 2010