Menu
Search

Forums

Forum Index

Thread overview
std.uni.CodepointSet from range of pairs of integers
February 19
Gravatar of Carl SturtivantPosted by Carl SturtivantReply
Carl Sturtivant
Gravatar of Carl Sturtivant


Reply

I wanted to construct a CodepointSet from a string, so I used the constructor here.
https://dlang.org/phobos/std_uni.html#.InversionList.this.2

I wrote a range of pairs (CodepointIntervals) of integers consisting of each codepoint in the string paired with that plus one. This did solve the problem, but only after I overcame some peculiarities of the situation.

Specifically, this required a forward range, not just an input range, so I wrote a save method.

Once I fixed that problem, it needed empty() and popFront() to be pure. So I added the word pure to each in my range.

Once I fixed that problem, it required those to be @safe, so I added that to my struct declaration of my range.

Then everything worked.

Could I have anticipated any of this, and what is the reason for each of these?

February 19
Gravatar of Richard (Rikki) Andrew CattermolePosted by Richard (Rikki) Andrew Cattermole
in reply to Carl Sturtivant		Reply
Richard (Rikki) Andrew Cattermole
Gravatar of Richard (Rikki) Andrew Cattermole
Posted in reply to Carl Sturtivant


Reply
I can understand ``pure``.

https://github.com/dlang/phobos/blob/master/std/uni/package.d#L2075

It is literally on the constructor.

Now @safe I don't know. My best guess would be for some reason the constructor is getting inferred as it (templates get inferred).
February 19
Gravatar of Carl SturtivantPosted by Carl Sturtivant
in reply to Richard (Rikki) Andrew Cattermole		Reply
Carl Sturtivant
Gravatar of Carl Sturtivant
Posted in reply to Richard (Rikki) Andrew Cattermole


Reply
On Monday, 19 February 2024 at 01:42:03 UTC, Richard (Rikki) Andrew Cattermole wrote:
> I can understand ``pure``.
>
> https://github.com/dlang/phobos/blob/master/std/uni/package.d#L2075
>
> It is literally on the constructor.
>
> Now @safe I don't know. My best guess would be for some reason the constructor is getting inferred as it (templates get inferred).

What about needing a forward range, not just an input range? It would seem it just needs to iterate through a sequence of pairs of integers.
February 19
Gravatar of Richard (Rikki) Andrew CattermolePosted by Richard (Rikki) Andrew Cattermole
in reply to Carl Sturtivant		Reply
Richard (Rikki) Andrew Cattermole
Gravatar of Richard (Rikki) Andrew Cattermole
Posted in reply to Carl Sturtivant


Reply
On 19/02/2024 5:33 PM, Carl Sturtivant wrote:
> On Monday, 19 February 2024 at 01:42:03 UTC, Richard (Rikki) Andrew Cattermole wrote:
>> I can understand ``pure``.
>>
>> https://github.com/dlang/phobos/blob/master/std/uni/package.d#L2075
>>
>> It is literally on the constructor.
>>
>> Now @safe I don't know. My best guess would be for some reason the constructor is getting inferred as it (templates get inferred).
> 
> What about needing a forward range, not just an input range? It would seem it just needs to iterate through a sequence of pairs of integers.

Indeed, nothing in that function body would suggest it needs to be a forward range.

Ah yup, the body was changed but never updated its template conditional.

https://github.com/dlang/phobos/commit/c9f1c42ed3a8bb92e48bf400ce2f31f434a99905
February 20
Gravatar of Carl SturtivantPosted by Carl Sturtivant
in reply to Richard (Rikki) Andrew Cattermole		Reply
Carl Sturtivant
Gravatar of Carl Sturtivant
Posted in reply to Richard (Rikki) Andrew Cattermole


Reply
On Monday, 19 February 2024 at 01:42:03 UTC, Richard (Rikki) Andrew Cattermole wrote:
> I can understand ``pure``.
>
> https://github.com/dlang/phobos/blob/master/std/uni/package.d#L2075
>
> It is literally on the constructor.

I should have noticed this!
February 20
Gravatar of Carl SturtivantPosted by Carl Sturtivant
in reply to Richard (Rikki) Andrew Cattermole		Reply
Carl Sturtivant
Gravatar of Carl Sturtivant
Posted in reply to Richard (Rikki) Andrew Cattermole


Reply
On Monday, 19 February 2024 at 04:47:07 UTC, Richard (Rikki) Andrew Cattermole wrote:
> On 19/02/2024 5:33 PM, Carl Sturtivant wrote:
>> On Monday, 19 February 2024 at 01:42:03 UTC, Richard (Rikki) Andrew Cattermole wrote:
>
> Indeed, nothing in that function body would suggest it needs to be a forward range.
>
> Ah yup, the body was changed but never updated its template conditional.
>
> https://github.com/dlang/phobos/commit/c9f1c42ed3a8bb92e48bf400ce2f31f434a99905

Thank you for looking into this.