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digitalmars.D.learn - traits getOverload of a template method

reply "QAston" <qaston gmail.com> writes:
How do i get aliases to overloads of a template method like

Class A
{
     int a(T)(T tq,T tw);
     int a(T)(T tq);
}
__traits(getOverloads, A, "a(int)")doesnt work
Feb 06 2014
next sibling parent ZombineDev <valid_email he.re> writes:
On Thursday, 6 February 2014 at 23:06:03 UTC, QAston wrote:

 How do i get aliases to overloads of a template method like

 Class A
 {
     int a(T)(T tq,T tw);
     int a(T)(T tq);
 }
 __traits(getOverloads, A, "a(int)")doesnt work


Bump. I also have a similar problem. I have a module with two 
function templates that are overloaded (they have the same name, 
but different sets of parameters) and I need to select one of 
them so I can cast it to a function with the  nogc attribute, 
similar to this: http://p0nce.github.io/d-idioms/#Bypassing- nogc.

```
// move has two overloads: `T move(T)(ref T)` and `void 
move(T)(ref T, ref T)`
// and I need to select the second one here:
cast(FT)(move!int)(arg1, arg2)

```
Otherwise I get "Error: template std.algorithm.mutation.move 
matches more than one template declaration".
Jan 26 2016
prev sibling next sibling parent reply Timoses <timosesu gmail.com> writes:
On Thursday, 6 February 2014 at 23:06:03 UTC, QAston wrote:

 How do i get aliases to overloads of a template method like

 Class A
 {
     int a(T)(T tq,T tw);
     int a(T)(T tq);
 }
 __traits(getOverloads, A, "a(int)")doesnt work


Is there any way to "select" overloaded template functions?

I require to select one of `std.bitmanip.peek`

     import std.bitmanip : peek;
     import std.system : Endian;
     alias myPeek = peek!(int, Endian.bigEndian, 
immutable(ubyte)[]);

Error:
template std.bitmanip.peek matches more than one template 
declaration:
/dlang/dmd/linux/bin64/../../src/phobos/std/bitmanip.d(3269):     
peek(T, Endian endianness = Endian.bigEndian, R)(R range) if 
(canSwapEndianness!T && isForwardRange!R && is(ElementType!R : 
const(ubyte)))
and
/dlang/dmd/linux/bin64/../../src/phobos/std/bitmanip.d(3306):     
peek(T, Endian endianness = Endian.bigEndian, R)(R range, size_t* 
index) if (canSwapEndianness!T && isForwardRange!R && 
hasSlicing!R && is(ElementType!R : const(ubyte)))

How to "select" one?
Sep 10 2018
parent reply aliak <something something.com> writes:
On Monday, 10 September 2018 at 12:57:25 UTC, Timoses wrote:

 On Thursday, 6 February 2014 at 23:06:03 UTC, QAston wrote:

 [...]


 Is there any way to "select" overloaded template functions?

 I require to select one of `std.bitmanip.peek`

     import std.bitmanip : peek;
     import std.system : Endian;
     alias myPeek = peek!(int, Endian.bigEndian, 
 immutable(ubyte)[]);

 Error:
 template std.bitmanip.peek matches more than one template 
 declaration:
 /dlang/dmd/linux/bin64/../../src/phobos/std/bitmanip.d(3269):
   peek(T, Endian endianness = Endian.bigEndian, R)(R range) if 
 (canSwapEndianness!T && isForwardRange!R && is(ElementType!R : 
 const(ubyte)))
 and
 /dlang/dmd/linux/bin64/../../src/phobos/std/bitmanip.d(3306):
   peek(T, Endian endianness = Endian.bigEndian, R)(R range, 
 size_t* index) if (canSwapEndianness!T && isForwardRange!R && 
 hasSlicing!R && is(ElementType!R : const(ubyte)))

 How to "select" one?


Can you either:

alias myPeek = () => peek!(int, Endian.bigEndian, 
immutable(ubyte)[])();
Or
alias myPeek = (size_t *index) => peek!(int, Endian.bigEndian, 
immutable(ubyte)[])(index);

??
Sep 10 2018
parent aliak <something something.com> writes:
On Monday, 10 September 2018 at 13:46:08 UTC, aliak wrote:

 On Monday, 10 September 2018 at 12:57:25 UTC, Timoses wrote:

 How to "select" one?


 Can you either:

 alias myPeek = () => peek!(int, Endian.bigEndian, 
 immutable(ubyte)[])();
 Or
 alias myPeek = (size_t *index) => peek!(int, Endian.bigEndian, 
 immutable(ubyte)[])(index);

 ??


With the Range arg as well of course.
Sep 10 2018
prev sibling parent Basile B. <b2.temp gmx.com> writes:
On Thursday, 6 February 2014 at 23:06:03 UTC, QAston wrote:

 How do i get aliases to overloads of a template method like

 Class A
 {
     int a(T)(T tq,T tw);
     int a(T)(T tq);
 }
 __traits(getOverloads, A, "a(int)")doesnt work


Support for template in the getOverloads trait has been added 
recently.
You have to set an optional trailing parameter to `true`:

```
class A
{
     int a(T)(T,T){}
     int a(T)(T){}
}

enum include_templates = true;
static foreach (overload; __traits(getOverloads, A, "a", 
include_templates))
     pragma(msg, overload.stringof);
```


 a(T)(T, T)
 a(T)(T)


specs: https://dlang.org/spec/traits.html#getOverloads
Sep 11 2018