Re: Static Associative Array
On 3/7/11, Jonathan M Davis wrote: > On Sunday 06 March 2011 18:33:04 Andrej Mitrovic wrote: >> On 3/7/11, Jonathan M Davis wrote: >> >> >> Kidding, just kidding.. > > That _did_ seem like a rather rude post for you... > > - Jonathan M Davis > Don't worry, I'd never be rude to my fellow D programmers out of the blue. Maybe that post was a semi-rant, but only half-serious. :) Anyway there's a nice SO post on enums here: http://stackoverflow.com/questions/4790652/enum-vs-immutable-in-d/4793684#4793684
Re: Static Associative Array
On 03/07/2011 03:22 AM, Peter Lundgren wrote:
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article
On Sunday 06 March 2011 14:05:04 Peter Lundgren wrote:
Can you define an associative array in a way that can be evaluated at
compile time like you can with non-associative arrays?
I'm pretty sure not. I think that it's currently suffering the same fate as
stuff
like classes and is not yet able to be CTFEed. Some day...
- Jonathan M Davis
If not, then what is the D way to initialize a static field of a struct or
class a
la Java's static initializer blocks? I don't mind constructing the associative
array at run-time if I have to, but I can't afford to do it more than the once
needed.
Use the module's clause:
int[string] aa;
static this () { aa = ["a":1, "b":2, "c":3]; }
unittest {
foreach (k,v ; aa)
writefln("%s --> %s", k,v);
}
Note: you can have as many such ckauses as you like.
Denis
--
_
vita es estrany
spir.wikidot.com
Re: Static Associative Array
On Sunday 06 March 2011 18:33:04 Andrej Mitrovic wrote: > On 3/7/11, Jonathan M Davis wrote: > > > Kidding, just kidding.. That _did_ seem like a rather rude post for you... - Jonathan M Davis
Re: Static Associative Array
On 3/7/11, Jonathan M Davis wrote: > Kidding, just kidding..
Re: Static Associative Array
Peter Lundgren:
> If not, then what is the D way to initialize a static field of a struct or
> class a
> la Java's static initializer blocks? I don't mind constructing the associative
> array at run-time if I have to, but I can't afford to do it more than the
> once needed.
Is this good enough?
struct Foo {
static int[int] aa;
static this() {
aa[0] = 1;
}
}
void main() {
assert(Foo.aa[0] == 1);
}
Bye,
bearophile
Re: Static Associative Array
On Sunday 06 March 2011 18:22:52 Peter Lundgren wrote:
> == Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article
>
> > On Sunday 06 March 2011 14:05:04 Peter Lundgren wrote:
> > > Can you define an associative array in a way that can be evaluated at
> > > compile time like you can with non-associative arrays?
> >
> > I'm pretty sure not. I think that it's currently suffering the same fate
> > as stuff like classes and is not yet able to be CTFEed. Some day...
> > - Jonathan M Davis
>
> If not, then what is the D way to initialize a static field of a struct or
> class a la Java's static initializer blocks? I don't mind constructing the
> associative array at run-time if I have to, but I can't afford to do it
> more than the once needed.
If you can initialize a field with CTFE, then you can do it directly.
Otherwise,
you have to do it with a constructor at runtime. If it's a member field of a
struct or class, then you use a normal constructor.
class C
{
this() { ... }
}
If it's a static field of a struct or class, then you use a static constructor
in
that struct or class.
class C
{
static this() { ... }
}
If it's a variable at the module level, then you use a module constructor (also
labeled with static).
static this() { ... }
- Jonathan M Davis
Re: Static Associative Array
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article > On Sunday 06 March 2011 14:05:04 Peter Lundgren wrote: > > Can you define an associative array in a way that can be evaluated at > > compile time like you can with non-associative arrays? > I'm pretty sure not. I think that it's currently suffering the same fate as > stuff > like classes and is not yet able to be CTFEed. Some day... > - Jonathan M Davis If not, then what is the D way to initialize a static field of a struct or class a la Java's static initializer blocks? I don't mind constructing the associative array at run-time if I have to, but I can't afford to do it more than the once needed.
Re: Static Associative Array
On Sunday 06 March 2011 16:30:00 Andrej Mitrovic wrote:
> What about:
>
> enum : string[int]
> {
> aa = [1: "blue", 2: "red"]
> }
>
> enum string s = aa[1];
>
> void main()
> {
> writeln(s);
> }
In both cases, the AA does not exist past compile time. That may be why it
works.
- Jonathan M Davis
Re: Static Associative Array
What about:
enum : string[int]
{
aa = [1: "blue", 2: "red"]
}
enum string s = aa[1];
void main()
{
writeln(s);
}
Re: Static Associative Array
Jonathan M Davis:
> I'm pretty sure not. I think that it's currently suffering the same fate as
> stuff
> like classes and is not yet able to be CTFEed. Some day...
This works:
import std.stdio;
string foo(int x) {
auto aa = [1: "hello", 2: "red"];
return aa[x];
}
enum string s = foo(1);
void main() {
writeln(s);
}
Bye,
bearophile
Re: Static Associative Array
On Sunday 06 March 2011 14:05:04 Peter Lundgren wrote: > Can you define an associative array in a way that can be evaluated at > compile time like you can with non-associative arrays? I'm pretty sure not. I think that it's currently suffering the same fate as stuff like classes and is not yet able to be CTFEed. Some day... - Jonathan M Davis
Static Associative Array
Can you define an associative array in a way that can be evaluated at compile time like you can with non-associative arrays?
