On Tuesday, 17 April 2012 at 14:57:18 UTC, Xan wrote:
On Tuesday, 17 April 2012 at 01:31:43 UTC, Kenji Hara wrote:
On Monday, 16 April 2012 at 18:48:52 UTC, Xan wrote:
On Sunday, 15 April 2012 at 19:30:27 UTC, Ali Çehreli wrote:
On 04/15/2012 11:39 AM, Xan wrote:
> On Sunday, 15 April 2012 at 11:23:37 UTC, John Chapman
> wrote:
>> On Sunday, 15 April 2012 at 11:16:43 UTC, Xan wrote:
>>>
>>> int main(string [] args)
>>> {
>>> auto alg = Algorisme!(int,int);
>>
>> Should be:
>> auto alg = new Algorisme!(int, int);
>>
>>> alg.nom = "Doblar";
>>> alg.versio = 1;
>>> alg.funcio = (int a) {return 2*a};
>>
>> Should be:
>> alg.funcio = (int a) { return 2 * a; };
>> or:
>> alg.funcio = a => 2 * a;
>>
>>> }
>
>
> It does not work:
>
> $ gdmd-4.6 algorisme.d
> algorisme.d:18: Error: variable algorisme.main.alg voids
> have
no value
> algorisme.d:18: Error: expression class Algorisme is void
> and
has no value
>
> with the code https://gist.github.com/2394274
>
> What fails now?
>
> Thanks,
> Xan.
Your code is still missing 'new':
auto alg = new Algorisme!(int, int);
With only this change, I receive this error:
$ gdmd-4.6 algorisme.d
algorisme.d:21: Error: cannot implicitly convert expression
(__dgliteral1) of type int delegate(int a) pure nothrow to
int function(int)
Unrelated recommendations:
- Return 0 from main() for successful exit, anything else by
convention means some sort of error.
- Take advantage of constructors (and 'alias') to simplify
syntax and risk of bugs:
import std.conv, std.stdio, std.stream, std.string;
import std.socket, std.socketstream;
import std.datetime;
class Algorisme(U,V) {
string nom;
uint versio;
alias V function (U) Funcio;
Funcio funcio;
this(string nom, uint versio, Funcio funcio)
{
this.nom = nom;
this.versio = versio;
this.funcio = funcio;
}
}
int main(string [] args)
{
alias Algorisme!(int, int) MeuAlgorism;
auto alg = new MeuAlgorism("Doblar", 1,
(int a) { return 2 * a; });
return 0;
}
Ali
With all of your suggestion
[https://gist.github.com/2394274], I get:
$ gdmd-4.6 algorisme.d
algorisme.d:30: Error: constructor
algorisme.Algorisme!(int,int).Algorisme.this (string nom,
uint versio, int function(int) funcio) is not callable using
argument types (string,int,int delegate(int a) pure nothrow)
algorisme.d:30: Error: cannot implicitly convert expression
(__dgliteral1) of type int delegate(int a) pure nothrow to
int function(int)
algorisme.d:27: Error: function D main has no return
statement, but is expected to return a value of type int
What fails?
PS: Thanks for your recommendations...
PPS: By the other hand, I see you have learned catalan
("MeuAlgorisme"?) ;-)
Problem may be here:
alg.funcio = (int a) { return 2 * a; };
2.057 and earlier (You may use gdc 2.057 and command line
wrapper gdmd), function literal always deduced as 'delegate'.
So this expression raises an error about type mismatching Lhs
of 'int function(int)' and Rhs of 'int delegate(int) pure
nothrow'.
Then, specifying explicit 'function' will resolve issue:
alg.funcio = function(int a) { return 2 * a; };
Bye.
Kenji Hara
Thanks, Kenji. If I change function to delegate in declaration
of field, it works too. What do you recommend to have delegates
or functions? What are the benefits and ...
Thanks,
Xan.
For an example, you can't use function-pointer to access
non-static methods, while with delegates you can. You can see
some examples on http://www.dlang.org (Languate Reference).
