Re: foreach for string[string]AA
On Wednesday, 1 March 2017 at 19:26:23 UTC, Mike Wey wrote: On 02/28/2017 07:16 PM, Anton Pastukhov wrote: On Tuesday, 28 February 2017 at 17:16:43 UTC, Daniel Kozák wrote: [...] Thank you for the link, it was informative reading. It's a pity that still there is no ordered AA at least as a library type. I had the same use case in the generator for GtkD, i needed fast lookup while iteration needed to preserve the insertion order. I opted for storing nodes of a linked list in the build in AA. The implementation[1] is currently LGPL to match the rest of the library, but if anyone would find it useful it can be changed to something else. [1] https://github.com/gtkd-developers/GtkD/blob/master/wrap/utils/LinkedHasMap.d Interesting. How this approach is compared to array of tuples performance-wise?
Re: foreach for string[string]AA
On Tuesday, 28 February 2017 at 17:16:43 UTC, Daniel Kozák wrote: V Tue, 28 Feb 2017 15:15:00 + Anton Pastukhov via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> napsáno: I can't see the logic in AA foreach order. Consider this code: ... Output: three two one four I was sure output should be one two three four https://forum.dlang.org/post/xbanhtkvrizyqjcib...@forum.dlang.org Thank you for the link, it was informative reading. It's a pity that still there is no ordered AA at least as a library type.
Re: foreach for string[string]AA
On Tuesday, 28 February 2017 at 15:44:46 UTC, bachmeier wrote: On Tuesday, 28 February 2017 at 15:33:46 UTC, ikod wrote: AA implemented as hash table, so it doesn't preserve insertion order. You have to sort keys when you need: import std.algorithm; import std.stdio; void main() { auto aa = ["one":1, "two":2 ]; foreach(k; sort(aa.keys)) { writeln(k); } } That will only work if sorting recovers the insertion order. An easy way to save the insertion order would be to use an array of structs. If an associate array is really needed, you can create a struct that contains the associative array and a string[] holding the keys. Thank you for quick replies. I'm used to arrays in PHP that are actually ordered maps, so I was expected the same from D's AAs. For now I'm fine with array of structs.
foreach for string[string]AA
I can't see the logic in AA foreach order. Consider this code: ``` void main() { string[string] test = [ "one": "1", "two": "2", "three": "3", "four": "4" ]; import std.stdio:writeln; foreach(k, v; test) { writeln(k); } } Output: three two one four I was sure output should be one two three four