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digitalmars.D - Is there a way to get the names of a function's parameters?

reply Adam Ruppe <destructionator gmail.com> writes:
Given:

void foo(int a, string b);

You can use std.traits.ParameterTypeTuple to get (int, string).

Is there any method, at all, to get ("a", "b") out of it? I can't find
one, and am considering import("mysrc.d"); and finding it that way,
but figured I'd ask first.

The benefits of getting the names would be runtime function calls, or
named arguments. Consider this:

ParameterTuple!foo args;

args.b = "hello";

foo(args);

That'd be kinda cool.
Jun 13 2010
next sibling parent BCS <none anon.com> writes:
Hello Adam,


 Given:
 
 void foo(int a, string b);
 
 You can use std.traits.ParameterTypeTuple to get (int, string).
 
 Is there any method, at all, to get ("a", "b") out of it? I can't find
 one, and am considering import("mysrc.d"); and finding it that way,
 but figured I'd ask first.
 



No need to parse the whole source:

http://codepad.org/ozZzC98d

-- 
... <IXOYE><
Jun 13 2010
prev sibling next sibling parent reply Jacob Carlborg <doob me.com> writes:
On 2010-06-14 00:56, Adam Ruppe wrote:

 Given:

 void foo(int a, string b);

 You can use std.traits.ParameterTypeTuple to get (int, string).

 Is there any method, at all, to get ("a", "b") out of it? I can't find
 one, and am considering import("mysrc.d"); and finding it that way,
 but figured I'd ask first.

 The benefits of getting the names would be runtime function calls, or
 named arguments. Consider this:

 ParameterTuple!foo args;

 args.b = "hello";

 foo(args);

 That'd be kinda cool.



Here you go: http://tango.pastebin.com/M38jdhGd including calling using 
named arguments.

-- 
/Jacob Carlborg
Jun 14 2010
parent Jacob Carlborg <doob me.com> writes:
On 2010-06-14 15:47, Simen kjaeraas wrote:

 Simen kjaeraas <simen.kjaras gmail.com> wrote:


 One needs to match parentheses from the last parentheses in the
 typeof.stringof.




 string parameterNamesOf( alias fn )( ) {
 string fullName = typeof(&fn).stringof;

 int pos = fullName.lastIndexOf( ')' );
 int end = pos;
 int count = 0;
 do {
 if ( fullName[pos] == ')' ) {
 count++;
 } else if ( fullName[pos] == '(' ) {
 count--;
 }
 pos--;
 } while ( count > 0 );

 return fullName[pos+2..end];
 }



Thanks.

-- 
/Jacob Carlborg
Jun 15 2010
prev sibling next sibling parent "Simen kjaeraas" <simen.kjaras gmail.com> writes:
Jacob Carlborg <doob me.com> wrote:


 Here you go: http://tango.pastebin.com/M38jdhGd including calling using  
 named arguments.



Does not handle function/delegate return types.

struct S {}
void function(int delegate(float)) F(string delegate(), string  
function(string, string), float, double, S);	
writeln("Parameters: ", parameterNamesOf!F);

Gives:
Parameters: delegate(float

One needs to match parentheses from the last parentheses in the  
typeof.stringof.

-- 
Simen
Jun 14 2010
prev sibling parent "Simen kjaeraas" <simen.kjaras gmail.com> writes:
Simen kjaeraas <simen.kjaras gmail.com> wrote:


 One needs to match parentheses from the last parentheses in the  
 typeof.stringof.




string parameterNamesOf( alias fn )( ) {
     string fullName = typeof(&fn).stringof;
	
     int pos = fullName.lastIndexOf( ')' );
     int end = pos;
     int count = 0;
     do {
         if ( fullName[pos] == ')' ) {
             count++;
         } else if ( fullName[pos] == '(' ) {
             count--;
         }
         pos--;
     } while ( count > 0 );
	
     return fullName[pos+2..end];
}

-- 
Simen
Jun 14 2010