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digitalmars.D - Associative arrays can't have a static array as key

reply Michiel <nomail hotmail.com> writes:
I have a template function like this:

void foo(T)(T bar) {
    int[T] bla;
    /* more code */
}

And I occasionally want to call it with a string literal.

foo("test");

But the compiler sais I can't, because "test" is of type char[4], and
apparently associative arrays can't take a static array as key.

This isn't documented. In fact, the documentation says that type[dim] can be
implicitly converted to type[].

But putting that aside for the moment, how can I convince D to automatically
make it a dynamic array, so I can use my function?

Thanks!
Feb 08 2007
parent reply "Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:
"Michiel" <nomail hotmail.com> wrote in message 
news:eqfctr$69r$1 digitaldaemon.com...


 But putting that aside for the moment, how can I convince D to 
 automatically
 make it a dynamic array, so I can use my function?



foo("blah"[]);

Notice the slice operator.  This converts the static array into a dynamic 
one.  Kind of ugly, but.
Feb 08 2007
next sibling parent Tomas Lindquist Olsen <tomas famolsen.dk> writes:
Jarrett Billingsley wrote:


 "Michiel" <nomail hotmail.com> wrote in message
 news:eqfctr$69r$1 digitaldaemon.com...
 

 But putting that aside for the moment, how can I convince D to
 automatically
 make it a dynamic array, so I can use my function?



 foo("blah"[]);
 
 Notice the slice operator.  This converts the static array into a dynamic
 one.  Kind of ugly, but.



Also:

foo("blah".dup);

will work.
Feb 08 2007
prev sibling parent reply Michiel <nomail hotmail.com> writes:
 foo("blah"[]);

 Notice the slice operator.  This converts the static array into a dynamic
 one.  Kind of ugly, but.



Hm.. Yes. That works. But I was hoping for a solution inside the function
definition, so i could still use regular string literals.
Feb 08 2007
parent "Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:
"Michiel" <nomail hotmail.com> wrote in message 
news:eqfeid$8mt$1 digitaldaemon.com...

 foo("blah"[]);

 Notice the slice operator.  This converts the static array into a dynamic
 one.  Kind of ugly, but.



 Hm.. Yes. That works. But I was hoping for a solution inside the function
 definition, so i could still use regular string literals.



import std.traits;

void foo(T)(T bar)
{
    static if(isStaticArray!(T))
        int[typeof(T[0])[]] bla;
    else
        int[T] bla;
    // ...
}

void main()
{
    foo("hi");
}


 :)
Feb 08 2007