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digitalmars.D.learn - Retrieving call expression of a function

reply Quentin Ladeveze <ladeveze.quentin openmailbox.org> writes:
Hi,

Is it possible to retrieve the calling expression of a function ? 
Something like that

---
import std.stdio;

void funcTest(int x, float y)
{
   writefln(get_call());
}

void main()
{
   float x = 0.2;
   funcTest(1+2, x+2);
}
---

output expected : " funcTest(1+2, x+2) "

Thanks
Nov 28 2015
parent reply tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:
On Saturday, 28 November 2015 at 15:02:32 UTC, Quentin Ladeveze 
wrote:

 Hi,

 Is it possible to retrieve the calling expression of a function 
 ? Something like that

 ---
 import std.stdio;

 void funcTest(int x, float y)
 {
   writefln(get_call());
 }

 void main()
 {
   float x = 0.2;
   funcTest(1+2, x+2);
 }
 ---

 output expected : " funcTest(1+2, x+2) "

 Thanks


I do not have right now to provide you with code, but three 
things:

1. Use of mixin,
2. The function call to be written in a string,
3. A wrapper that stores given function call string, saves it, 
and mixin it.
Nov 28 2015
parent reply Quentin Ladeveze <ladeveze.quentin openmailbox.org> writes:
On Saturday, 28 November 2015 at 15:22:51 UTC, tcak wrote:

 On Saturday, 28 November 2015 at 15:02:32 UTC, Quentin Ladeveze 
 wrote:

 Hi,

 Is it possible to retrieve the calling expression of a 
 function ? Something like that

 ---
 import std.stdio;

 void funcTest(int x, float y)
 {
   writefln(get_call());
 }

 void main()
 {
   float x = 0.2;
   funcTest(1+2, x+2);
 }
 ---

 output expected : " funcTest(1+2, x+2) "

 Thanks


 I do not have right now to provide you with code, but three 
 things:

 1. Use of mixin,
 2. The function call to be written in a string,
 3. A wrapper that stores given function call string, saves it, 
 and mixin it.


Thanks, it was a cool idea, I made something that works, but you 
can only call the function with literals, not with variables :

---

import std.stdio;

void main()
{
	int x = 2;

	enum call = "funcTest(1, 0.2);";
  	callPrinter!call;
}

template callPrinter(string call)
{
	void callPrinter()
	{
		writeln(call);
		mixin(call);
	}
}

void funcTest(int x, float y)
{
	writeln("called with ", x, " and ", y);
}

---

output :
funcTest(2, 0.2);
called with 2 and 0.2
Nov 28 2015
parent reply tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:
On Saturday, 28 November 2015 at 15:41:59 UTC, Quentin Ladeveze 
wrote:

 On Saturday, 28 November 2015 at 15:22:51 UTC, tcak wrote:

 On Saturday, 28 November 2015 at 15:02:32 UTC, Quentin 
 Ladeveze wrote:

 Hi,

 Is it possible to retrieve the calling expression of a 
 function ? Something like that

 ---
 import std.stdio;

 void funcTest(int x, float y)
 {
   writefln(get_call());
 }

 void main()
 {
   float x = 0.2;
   funcTest(1+2, x+2);
 }
 ---

 output expected : " funcTest(1+2, x+2) "

 Thanks


 I do not have right now to provide you with code, but three 
 things:

 1. Use of mixin,
 2. The function call to be written in a string,
 3. A wrapper that stores given function call string, saves it, 
 and mixin it.


 Thanks, it was a cool idea, I made something that works, but 
 you can only call the function with literals, not with 
 variables :

 ---

 import std.stdio;

 void main()
 {
 	int x = 2;

 	enum call = "funcTest(1, 0.2);";
  	callPrinter!call;
 }

 template callPrinter(string call)
 {
 	void callPrinter()
 	{
 		writeln(call);
 		mixin(call);
 	}
 }

 void funcTest(int x, float y)
 {
 	writeln("called with ", x, " and ", y);
 }

 ---

 output :
 funcTest(2, 0.2);
 called with 2 and 0.2


mixin template could solve this problem as well I guess. It 
would, instead of calling a function, directly inject the code 
into where you call it. So, remove the callPrinter function, make 
template a mixin template, and in main, call it like mixin 
callPrinter!"...";
Nov 28 2015
parent Quentin Ladeveze <ladeveze.quentin openmailbox.org> writes:
On Saturday, 28 November 2015 at 17:19:40 UTC, tcak wrote:

 On Saturday, 28 November 2015 at 15:41:59 UTC, Quentin Ladeveze 
 wrote:

 [...]


 mixin template could solve this problem as well I guess. It 
 would, instead of calling a function, directly inject the code 
 into where you call it. So, remove the callPrinter function, 
 make template a mixin template, and in main, call it like mixin 
 callPrinter!"...";


I don't think mixin templates would work here. The reference says 
that we can only do declarations in a mixin template.
Nov 28 2015