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digitalmars.D.learn - How can I express the type of a function in D?

reply Sobaya <sobaya007 gmail.com> writes:
I want to get a mangled name of a D function by 
`core.demangle.mangle`, but I'm in trouble because there are no 
ways to express a type of a function, which is used for a 
template argument of `mangle`.

For example, it is wrong to use the type `int function(int,int)` 
to express the type of `int add(int,int)`.
Because it expresses the type of a function POINTER, not just a 
function.

The fuction name in a binary compiled this function is 
"_D3addFiiZi", but `mangle!(int function(int,int))("add")` 
returns "_D3addPFiiZi", which includes "P" meaning POINTER.

How can I get the former one?

Thanks.
Jan 29 2019
next sibling parent reply FrankLike <1150015857 qq.com> writes:
On Wednesday, 30 January 2019 at 05:14:20 UTC, Sobaya wrote:

 I want to get a mangled name of a D function by 
 `core.demangle.mangle`, but I'm in trouble because there are no 
 ways to express a type of a function, which is used for a 
 template argument of `mangle`.

 For example, it is wrong to use the type `int 
 function(int,int)` to express the type of `int add(int,int)`.
 Because it expresses the type of a function POINTER, not just a 
 function.

 The fuction name in a binary compiled this function is 
 "_D3addFiiZi", but `mangle!(int function(int,int))("add")` 
 returns "_D3addPFiiZi", which includes "P" meaning POINTER.

 How can I get the former one?

 Thanks.


import std.stdio;
alias int*  PINT;

void main()
{
	auto x= Add(1,2);
	writeln(x);
	writeln(&x);
	executeShell("pause");
}

private PINT Add(int a,int b)
{
	return cast(PINT)(a+b);
}

////////////////CODE END//////////
It works ok.
Jan 29 2019
parent reply FrankLike <1150015857 qq.com> writes:
On Wednesday, 30 January 2019 at 05:40:50 UTC, FrankLike wrote:

 On Wednesday, 30 January 2019 at 05:14:20 UTC, Sobaya wrote:

 I want to get a mangled name of a D function by 
 `core.demangle.mangle`, but I'm in trouble because there are 
 no ways to express a type of a function, which is used for a 
 template argument of `mangle`.

 For example, it is wrong to use the type `int 
 function(int,int)` to express the type of `int add(int,int)`.
 Because it expresses the type of a function POINTER, not just 
 a function.

 The fuction name in a binary compiled this function is 
 "_D3addFiiZi", but `mangle!(int function(int,int))("add")` 
 returns "_D3addPFiiZi", which includes "P" meaning POINTER.

 How can I get the former one?

 Thanks.




import std.stdio;
import std.process:executeShell;
import core.demangle;

void main()
{	
	assert(mangle!(int function(int))("a.b") == "_D1a1bPFiZi");
	executeShell("pause");
}

 ////////////////CODE END//////////
 Yes,"_D1a1bPFiZi",which includes "P".
Jan 29 2019
parent Sobaya <sobaya007 gmail.com> writes:
On Wednesday, 30 January 2019 at 06:02:02 UTC, FrankLike wrote:

 On Wednesday, 30 January 2019 at 05:40:50 UTC, FrankLike wrote:

 On Wednesday, 30 January 2019 at 05:14:20 UTC, Sobaya wrote:

 [...]




 import std.stdio;
 import std.process:executeShell;
 import core.demangle;

 void main()
 {	
 	assert(mangle!(int function(int))("a.b") == "_D1a1bPFiZi");
 	executeShell("pause");
 }

 ////////////////CODE END//////////
 Yes,"_D1a1bPFiZi",which includes "P".




I want a mangled function name without "P", not one with "P".
Jan 29 2019
prev sibling next sibling parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/29/2019 09:14 PM, Sobaya wrote:

 I want to get a mangled name of a D function by `core.demangle.mangle`, 
 but I'm in trouble because there are no ways to express a type of a 
 function, which is used for a template argument of `mangle`.
 
 For example, it is wrong to use the type `int function(int,int)` to 
 express the type of `int add(int,int)`.
 Because it expresses the type of a function POINTER, not just a function.
 
 The fuction name in a binary compiled this function is "_D3addFiiZi", 
 but `mangle!(int function(int,int))("add")` returns "_D3addPFiiZi", 
 which includes "P" meaning POINTER.
 
 How can I get the former one?
 
 Thanks.
 


typeof works:

import core.demangle;

int add(int, int);

void main() {
   alias F = typeof(add);
   pragma(msg, mangle!F("add"));
}

Ali
Jan 30 2019
prev sibling next sibling parent reply Steven Schveighoffer <schveiguy gmail.com> writes:
On 1/30/19 12:14 AM, Sobaya wrote:

 I want to get a mangled name of a D function by `core.demangle.mangle`, 
 but I'm in trouble because there are no ways to express a type of a 
 function, which is used for a template argument of `mangle`.
 
 For example, it is wrong to use the type `int function(int,int)` to 
 express the type of `int add(int,int)`.
 Because it expresses the type of a function POINTER, not just a function.
 
 The fuction name in a binary compiled this function is "_D3addFiiZi", 
 but `mangle!(int function(int,int))("add")` returns "_D3addPFiiZi", 
 which includes "P" meaning POINTER.
 
 How can I get the former one?


Why not use add.mangleof?

-Steve
Jan 30 2019
parent reply =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/30/2019 07:47 AM, Steven Schveighoffer wrote:

 On 1/30/19 12:14 AM, Sobaya wrote:

 I want to get a mangled name of a D function by
 `core.demangle.mangle`, but I'm in trouble because there are no ways
 to express a type of a function, which is used for a template argument
 of `mangle`.

 For example, it is wrong to use the type `int function(int,int)` to
 express the type of `int add(int,int)`.
 Because it expresses the type of a function POINTER, not just a 




function.

 The fuction name in a binary compiled this function is "_D3addFiiZi",
 but `mangle!(int function(int,int))("add")` returns "_D3addPFiiZi",
 which includes "P" meaning POINTER.

 How can I get the former one?


 Why not use add.mangleof?

 -Steve


add.mangleof includes the module name as well (_D6deneme3addFiiZi) but 
the OP wanted without (_D3addFiiZi). I wonder why the inconsistency. On 
the other hand, .mangleof produces just "add" when the function is 
extern(C). (?)

import core.demangle;

extern(C) int add(int, int);

void main() {
   alias F = typeof(add);
   pragma(msg, mangle!F("add"));
   pragma(msg, add.mangleof);
}

Output:

_D3addUiiZi
add               <-- Is that correct?

Ali
Jan 30 2019
next sibling parent reply "H. S. Teoh" <hsteoh quickfur.ath.cx> writes:
On Wed, Jan 30, 2019 at 10:39:21AM -0800, Ali Çehreli via Digitalmars-d-learn
wrote:
[...]

 I wonder why the inconsistency. On the other hand, .mangleof produces
 just "add" when the function is extern(C).  (?)


[...]

For extern(C), this is correct behaviour, because that's how a C
function would be mangled (i.e., not mangled at all).


T

-- 
In a world without fences, who needs Windows and Gates? -- Christian Surchi
Jan 30 2019
parent reply =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/30/2019 11:42 AM, H. S. Teoh wrote:

 On Wed, Jan 30, 2019 at 10:39:21AM -0800, Ali Çehreli via Digitalmars-d-learn
wrote:
 [...]

 I wonder why the inconsistency. On the other hand, .mangleof produces
 just "add" when the function is extern(C).  (?)


 [...]
 
 For extern(C), this is correct behaviour, because that's how a C
 function would be mangled (i.e., not mangled at all).
 
 
 T
 


I remember names like _add. Is that a Windows thing?

Ali
Jan 30 2019
parent Neia Neutuladh <neia ikeran.org> writes:
On Wed, 30 Jan 2019 12:56:06 -0800, Ali Çehreli wrote:

 I remember names like _add. Is that a Windows thing?


A number of functions are implemented as manually-mangled names with 
preprocessor macros that forward to them. It's weird, but it happens.
Jan 30 2019
prev sibling next sibling parent reply Neia Neutuladh <neia ikeran.org> writes:
On Wed, 30 Jan 2019 10:39:21 -0800, Ali Çehreli wrote:

 import core.demangle;
 
 extern(C) int add(int, int);
 
 void main() {
    alias F = typeof(add);
    pragma(msg, mangle!F("add"));
    pragma(msg, add.mangleof);
 }
 
 Output:
 
 _D3addUiiZi
 add               <-- Is that correct?


`add.mangleof` is correct. In fact, it's definitively correct.

typeof(add) is extern(C) int function(int, int). Based on this output, 
core.demangle seems like it's not taking the extern(C) portion into 
account.
Jan 30 2019
parent "H. S. Teoh" <hsteoh quickfur.ath.cx> writes:
On Wed, Jan 30, 2019 at 07:51:17PM +0000, Neia Neutuladh via
Digitalmars-d-learn wrote:

 On Wed, 30 Jan 2019 10:39:21 -0800, Ali Çehreli wrote:

 import core.demangle;
 
 extern(C) int add(int, int);
 
 void main() {
    alias F = typeof(add);
    pragma(msg, mangle!F("add"));
    pragma(msg, add.mangleof);
 }
 
 Output:
 
 _D3addUiiZi
 add               <-- Is that correct?


 
 `add.mangleof` is correct. In fact, it's definitively correct.
 
 typeof(add) is extern(C) int function(int, int). Based on this output,
 core.demangle seems like it's not taking the extern(C) portion into
 account.


That would be a bug in core.demangle.


T

-- 
"I suspect the best way to deal with procrastination is to put off the
procrastination itself until later. I've been meaning to try this, but haven't
gotten around to it yet. " -- swr
Jan 30 2019
prev sibling parent Steven Schveighoffer <schveiguy gmail.com> writes:
On 1/30/19 1:39 PM, Ali Çehreli wrote:

 On 01/30/2019 07:47 AM, Steven Schveighoffer wrote:
  > On 1/30/19 12:14 AM, Sobaya wrote:
  >> I want to get a mangled name of a D function by
  >> `core.demangle.mangle`, but I'm in trouble because there are no ways
  >> to express a type of a function, which is used for a template argument
  >> of `mangle`.
  >>
  >> For example, it is wrong to use the type `int function(int,int)` to
  >> express the type of `int add(int,int)`.
  >> Because it expresses the type of a function POINTER, not just a 
 function.
  >>
  >> The fuction name in a binary compiled this function is "_D3addFiiZi",
  >> but `mangle!(int function(int,int))("add")` returns "_D3addPFiiZi",
  >> which includes "P" meaning POINTER.
  >>
  >> How can I get the former one?
  >
  > Why not use add.mangleof?
  >
 
 add.mangleof includes the module name as well (_D6deneme3addFiiZi) but 
 the OP wanted without (_D3addFiiZi). 


But he says `The fuction name in a binary compiled this function is 
"_D3addFiiZi"`. So whatever he compiles as must be what mangleof 
reports, as it's the same entity generating the mangle. I don't know 
what his source code is.

-Steve
Jan 30 2019
prev sibling next sibling parent Atila Neves <atila.neves gmail.com> writes:
On Wednesday, 30 January 2019 at 05:14:20 UTC, Sobaya wrote:

 I want to get a mangled name of a D function by 
 `core.demangle.mangle`, but I'm in trouble because there are no 
 ways to express a type of a function, which is used for a 
 template argument of `mangle`.


There's a way:

int add(int i, int j);
static assert(is(typeof(add) == typeof(*(int function(int, 
int)).init)));

Unfortunately there's no dedicated syntax for it, unlike C++. 
Weirdly enough, if you pragma(msg) a function type it prints it 
out in C++ syntax (e.g. `int(int, int)`), but if you type it 
yourself it won't compile.

Then there's this oddity:

https://issues.dlang.org/show_bug.cgi?id=19270
Feb 01 2019
prev sibling parent dnsmt <null dnsmt.nl> writes:
On Wednesday, 30 January 2019 at 05:14:20 UTC, Sobaya wrote:

 I want to get a mangled name of a D function by 
 `core.demangle.mangle`, but I'm in trouble because there are no 
 ways to express a type of a function, which is used for a 
 template argument of `mangle`.


Did you consider `core.demangle.mangleFunc` instead?
Feb 04 2019