• Weed (9/9) Dec 26 2008 Can I at compile time check whether there is a facility method
• Simen Kjaeraas (9/18) Dec 26 2008 I believe this works:
• Bill Baxter (4/23) Dec 26 2008 Additionally, in D2 I think you can do this: __traits(compiles,
• Bill Baxter (19/19) Dec 27 2008 MjAwOC8xMi8yNyBXZWVkIDxyZXN1bWU3NTVAbWFpbC5ydT46Cj4gU2ltZW4gS2phZXJhYXMg...
• Weed (3/38) Dec 27 2008 There was confusion between this.toString () and std.stdio.toString ()

Weed <resume755 mail.ru> writes:

Can I at compile time check whether there is a facility method
(toString(), for example)?

Today I wrote:

                static if ( __traits(isArithmetic, Element) ) {
                    ret ~= toString(this[i,j]) ~ "\t";
                } else {
                    ret ~= this[i,j].toString ~ "\t";
                }

It works but it is wrong

"Simen Kjaeraas" <simen.kjaras gmail.com> writes:

On Fri, 26 Dec 2008 20:15:30 +0100, Weed <resume755 mail.ru> wrote:

 Can I at compile time check whether there is a facility method
 (toString(), for example)?

 Today I wrote:

                 static if ( __traits(isArithmetic, Element) ) {
                     ret ~= toString(this[i,j]) ~ "\t";
                 } else {
                     ret ~= this[i,j].toString ~ "\t";
                 }

 It works but it is wrong

I believe this works:

static if (is(typeof(this[i,j].toString))) {
	ret ~= this[i,j].toString;
} else {
	ret ~= toString(this[i,j]);
}

-- 
Simen

"Bill Baxter" <wbaxter gmail.com> writes:

On Sat, Dec 27, 2008 at 6:30 AM, Simen Kjaeraas <simen.kjaras gmail.com> wrote:
 On Fri, 26 Dec 2008 20:15:30 +0100, Weed <resume755 mail.ru> wrote:

 Can I at compile time check whether there is a facility method
 (toString(), for example)?

 Today I wrote:

                static if ( __traits(isArithmetic, Element) ) {
                    ret ~= toString(this[i,j]) ~ "\t";
                } else {
                    ret ~= this[i,j].toString ~ "\t";
                }

 It works but it is wrong

 I believe this works:

 static if (is(typeof(this[i,j].toString))) {
        ret ~= this[i,j].toString;
 } else {
        ret ~= toString(this[i,j]);
 }

Additionally, in D2 I think you can do this:   __traits(compiles,
this[i,j].toString)

--bb

"Bill Baxter" <wbaxter gmail.com> writes:

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Weed <resume755 mail.ru> writes:

Bill Baxter ÐÉÛÅÔ:
 2008/12/27 Weed <resume755 mail.ru>:
 Simen Kjaeraas ÐÉÛÅÔ:
 On Fri, 26 Dec 2008 20:15:30 +0100, Weed <resume755 mail.ru> wrote:

 Can I at compile time check whether there is a facility method
 (toString(), for example)?

 Today I wrote:

                 static if ( __traits(isArithmetic, Element) ) {
                     ret ~= toString(this[i,j]) ~ "\t";
                 } else {
                     ret ~= this[i,j].toString ~ "\t";
                 }

 It works but it is wrong

 I believe this works:

 static if (is(typeof(this[i,j].toString))) {
     ret ~= this[i,j].toString;
 } else {
     ret ~= toString(this[i,j]);
 }

 No, this cause error:

 toString () does not match parameter types (float)

 ( condition is always resolved to else {...} )

 
 That's because float's don't have a toString method.  So it should be
 picking the else{} case.
 
 If you try it with something where this[i,j] returns an Object or
 struct with a toString, then it should pick the 'if' branch.


There was confusion between this.toString () and std.stdio.toString ()

Fixed, thanks!