Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On 03/03/2016 05:17 AM, Andrew Edwards wrote:
> On 3/3/16 7:01 PM, MGW wrote:
>> immutable long[string] aa = [
>> "foo": 5,
>> "bar": 10,
>> "baz": 2000
>> ];
>
> The only way this can be done outside the body of a function is if it is
> a manifest constant. This works:
>
> enum long[string] aa = [
> "foo": 5,
> "bar": 10,
> "baz": 2000
> ];
With the caveat that 'aa' is a manifest constant, meaning that its
values will be placed everywhere 'aa' appears in code. So, the following
loop *creates* an associative array at avery iteration:
while (/* ... */) {
if (aa[s] == 5) { // <-- oops :(
// ...
}
}
I think initializing it in a 'shared static this()' (or 'static this()')
block is better:
immutable long[string] aa;
shared static this() {
aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
}
void main() {
assert(aa["foo"] == 5);
}
Ali
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On 3/3/16 7:01 PM, MGW wrote: immutable long[string] aa = [ "foo": 5, "bar": 10, "baz": 2000 ]; The only way this can be done outside the body of a function is if it is a manifest constant. This works: enum long[string] aa = [ "foo": 5, "bar": 10, "baz": 2000 ];
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On Thursday, 3 March 2016 at 10:35:50 UTC, MGW wrote:
The citation from https://dlang.org/spec/hash-map.html
Static Initialization of AAs
immutable long[string] aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
unittest
{
assert(aa["foo"] == 5);
assert(aa["bar"] == 10);
assert(aa["baz"] == 2000);
}
Judging by the text, it is static initialization, during
compilation.
You have to put that definition inside body of a function (a
declaration). it should not be placed inside module's root level
code.
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On Thursday, 3 March 2016 at 10:35:50 UTC, MGW wrote:
The citation from https://dlang.org/spec/hash-map.html
Static Initialization of AAs
immutable long[string] aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
unittest
{
assert(aa["foo"] == 5);
assert(aa["bar"] == 10);
assert(aa["baz"] == 2000);
}
Judging by the text, it is static initialization, during
compilation.
Hey your right! https://dlang.org/spec/hash-map.html
I don't actually understand D that much but runtime logic made
sense...
That unit test passes somehow, perhaps because unit test are
executed? Looks like a bug in the test and/or documentation!
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
The citation from https://dlang.org/spec/hash-map.html
Static Initialization of AAs
immutable long[string] aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
unittest
{
assert(aa["foo"] == 5);
assert(aa["bar"] == 10);
assert(aa["baz"] == 2000);
}
Judging by the text, it is static initialization, during
compilation.
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On Thursday, 3 March 2016 at 10:01:47 UTC, MGW wrote:
immutable long[string] aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
... Error: non-constant expression ["foo":5L, "bar":10L,
"baz":2000L]
D associative arrays are a dynamic runtime feature, thus can't be
initialized without runtime expressions. :(
This ended up failing too:
struct slot_t { char* key; long value; };
slot_t bogus[3] = {
{ "foo", 5L },
{ "bar", 10L },
{ "baz", 2000L }
};
import std.stdio;
void main() {
bogus.map.writeln();
}
Re: Error with associative array initializer DMD32 D Compiler v2.070.0
On Thursday, 3 March 2016 at 10:01:47 UTC, MGW wrote:
immutable long[string] aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
... Error: non-constant expression ["foo":5L, "bar":10L,
"baz":2000L]
I'm not sure there's a way around this except by initialising it
at runtime. So you can't get it in the rom segment.
immutable long[string] aa;
shared static this() {
aa = [
"foo": 5,
"bar": 10,
"baz": 2000
];
}
Error with associative array initializer DMD32 D Compiler v2.070.0
immutable long[string] aa = [ "foo": 5, "bar": 10, "baz": 2000 ]; ... Error: non-constant expression ["foo":5L, "bar":10L, "baz":2000L]
