Operator overloading

[Dmitry Olshansky]

On 19.04.2012 23:14, Xan wrote:
> Hi, I read http://dlang.org/operatoroverloading.html but in my code it
> does not work. I tried to overload '*' binary operator in my class
> Algorisme:
>
> [...]
> class Algorisme(U,V) {
> string nom;
> uint versio;
> alias V function (U) Funcio;
> Funcio funcio;
>
> this(string nom, uint versio, Funcio funcio) {
> try {
> this.nom = nom;
> this.versio = versio;
> this.funcio = funcio;
> }
> catch {
> writeln("Error");
> }
> }
>
> string toString() {
> return format("%s (versió %s): %s -> %s", nom, versio, typeid(U),
> typeid(V));
> }
>
> Algorisme(U, V) opBinary(string op) (Algorisme(U, V) alg) {
Algorisme! opBinary(string op) (Algorisme alg) {

or
Algorisme!(U,V) opBinary(string op) (Algorisme!(U,V) alg) {

should do it

static if (op == '*') return new Algorisme("composició",

or:
static if (op == '*') return new Algorisme!(U,v)("composició",

same here. There is no need to put !(params) explicitly if it's the same 
as the template you are writing.

> this.versio+alg.versio, this.funcio);
> }
>
> }
> [...]
>
> but I receive these errors:
>
> $ gdmd-4.6 algorisme.d
> algorisme.d:31: function declaration without return type. (Note that
> constructors are always named 'this')
> algorisme.d:31: no identifier for declarator Algorisme(U, V)
> algorisme.d:31: semicolon expected following function declaration
> algorisme.d:31: function declaration without return type. (Note that
> constructors are always named 'this')
> algorisme.d:31: function declaration without return type. (Note that
> constructors are always named 'this')
> algorisme.d:31: found 'alg' when expecting ')'
> algorisme.d:31: no identifier for declarator opBinary(Algorisme(U, V))
> algorisme.d:31: semicolon expected following function declaration
> algorisme.d:31: Declaration expected, not ')'
> algorisme.d:35: unrecognized declaration
>
>
> Why it fails?
> Anyone could help me?
>
> Thanks,
> Xan.


-- 
Dmitry Olshansky