Re: template instance cannot use local 'f' as parameter to non-global template

[Trass3r]

Anybody an idea?

Re: template instance cannot use local 'f' as parameter to non-global template

[Stephan]

On 12.07.2011 15:06, Trass3r wrote:

Is this a bug? If not, how do you make it work?

void h() {}

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(alias g = f)()
{
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

test.d(18): Error: template instance cannot use local 'f' as parameter
to non-global template blub(alias g = f)
test.d(18): Error: template instance forward reference of f
test.d(18): Error: template instance test.Bla.wrap!(h).blub!(f) error
instantiating


I am not sure but i am not that used to those template aliases anyway.

Re: template instance cannot use local 'f' as parameter to non-global template

[Steven Schveighoffer]

On Tue, 12 Jul 2011 09:06:56 -0400, Trass3r u...@known.com wrote:


Is this a bug? If not, how do you make it work?

void h() {}

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(alias g = f)()
{
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

test.d(18): Error: template instance cannot use local 'f' as parameter  
to non-global template blub(alias g = f)

test.d(18): Error: template instance forward reference of f
test.d(18): Error: template instance test.Bla.wrap!(h).blub!(f) error  
instantiating


I've seen this error before...

*searches memory and old code*

Here you go: http://d.puremagic.com/issues/show_bug.cgi?id=3051

As a workaround, is there a reason you need blub to be parameterized?  I  
mean, f is already part of the template.


-Steve

Re: template instance cannot use local 'f' as parameter to non-global template

[Trass3r]

Am 13.07.2011, 16:02 Uhr, schrieb Steven Schveighoffer  
schvei...@yahoo.com:



void h() {}

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(alias g = f)()
{

g();

}
}


As a workaround, is there a reason you need blub to be parameterized?  I  
mean, f is already part of the template.


Yep, a default function is passed to wrap and in most cases blub just  
calls that one.

But sometimes I need blub to use a function other than the default one.

Re: template instance cannot use local 'f' as parameter to non-global template

[Tyro[a.c.edwards]]

On 7/13/2011 11:35 PM, Trass3r wrote:

Am 13.07.2011, 16:02 Uhr, schrieb Steven Schveighoffer
schvei...@yahoo.com:


void h() {}

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(alias g = f)()
{

g();

}
}



As a workaround, is there a reason you need blub to be parameterized?
I mean, f is already part of the template.


Yep, a default function is passed to wrap and in most cases blub just
calls that one.
But sometimes I need blub to use a function other than the default one.


Don't know it this is the right answer or a possible bug but it does the 
trick:


void h() { import std.stdio; write(h()); }

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(typeof(f) g = f)
{
g();
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

Re: template instance cannot use local 'f' as parameter to non-global template

[Trass3r]

Am 13.07.2011, 16:58 Uhr, schrieb Tyro[a.c.edwards] nos...@home.com:
Don't know it this is the right answer or a possible bug but it does the  
trick:


void h() { import std.stdio; write(h()); }

class Bla
{
 mixin wrap!h;
}

mixin template wrap(alias f)
{
 void blub(typeof(f) g = f)
 {
g();
 }
}

void main()
{
 Bla b = new Bla();
 b.blub();
}


Thanks!
Unfortunately it doesn't work with more complex functions:

Error: arithmetic/string type expected for value-parameter, not cl_errcode  
C function(cl_program program, uint param_name, ulong param_value_size,  
void* param_value, ulong* param_value_size_ret)

Re: template instance cannot use local 'f' as parameter to non-global template

[Trass3r]

I've seen this error before...

*searches memory and old code*

Here you go: http://d.puremagic.com/issues/show_bug.cgi?id=3051


I think this is yet another issue.
The inner template argument is not something on the stack but it is a  
template argument.

Re: template instance cannot use local 'f' as parameter to non-global template

[Tyro[a.c.edwards]]

On 7/14/2011 12:24 AM, Trass3r wrote:

Am 13.07.2011, 16:58 Uhr, schrieb Tyro[a.c.edwards] nos...@home.com:

Don't know it this is the right answer or a possible bug but it does
the trick:

void h() { import std.stdio; write(h()); }

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(typeof(f) g = f)
{
g();
}
}

void main()
{
Bla b = new Bla();
b.blub();
}


Thanks!
Unfortunately it doesn't work with more complex functions:

Error: arithmetic/string type expected for value-parameter, not
cl_errcode C function(cl_program program, uint param_name, ulong
param_value_size, void* param_value, ulong* param_value_size_ret)



I gusss the simplest example of the problem you're experiencing would be 
this:


void h() { import std.stdio; write(h()); }

void function() fp = h;

class Bla
{
mixin wrap!(fp);
}

mixin template wrap(alias f)
{
void blub()
{
typeof(f) g = f;
g();  // --- source of error [1]
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

edit1.d(19): Error: function expected before (), not g of type uint* C 
function()*


[1] Here you are calling a function pointer which simply returns the 
address of the function... hence your error!


Try calling the function (differencing the pointer as such: (*g)()) and 
your problem is solved.

Re: template instance cannot use local 'f' as parameter to non-global template

[Tyro[a.c.edwards]]

On 7/14/2011 12:24 AM, Trass3r wrote:

Am 13.07.2011, 16:58 Uhr, schrieb Tyro[a.c.edwards] nos...@home.com:

Don't know it this is the right answer or a possible bug but it does
the trick:

void h() { import std.stdio; write(h()); }

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(typeof(f) g = f)
{
g();
}
}

void main()
{
Bla b = new Bla();
b.blub();
}


Thanks!
Unfortunately it doesn't work with more complex functions:

Error: arithmetic/string type expected for value-parameter, not
cl_errcode C function(cl_program program, uint param_name, ulong
param_value_size, void* param_value, ulong* param_value_size_ret)


I guess the simplest example of the problem you're experiencing would be 
this:


void h() { import std.stdio; write(h()); }

void function() fp = h;

class Bla
{
mixin wrap!(fp);
}

mixin template wrap(alias f)
{
void blub()
{
typeof(f) g = f;
g();  // --- source of error [1]
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

edit1.d(19): Error: function expected before (), not g of type void 
function()*


[1] Here you are calling a function pointer which simply returns the 
address of the function... hence your error!


Try calling the function pointed to by differencing the pointer as such: 
(*g)() and your problem is solved.

template instance cannot use local 'f' as parameter to non-global template

[Trass3r]

Is this a bug? If not, how do you make it work?

void h() {}

class Bla
{
mixin wrap!h;
}

mixin template wrap(alias f)
{
void blub(alias g = f)()
{
}
}

void main()
{
Bla b = new Bla();
b.blub();
}

test.d(18): Error: template instance cannot use local 'f' as parameter to  
non-global template blub(alias g = f)

test.d(18): Error: template instance forward reference of f
test.d(18): Error: template instance test.Bla.wrap!(h).blub!(f) error  
instantiating