> On Apr 25, 2022, at 8:27 PM, Hairy Pixels <[email protected]> wrote:
>
>> For some reason I don't get all mails by Ryan, so I reply here:
>>
>> Helpers currently can't be generic and even if they could be (which I do
>> plan to add) it would require an explicit specialization of the helper to be
>> used because the compiler will not be tasked with searching for potential
>> generic helpers and then implicitly specializing a whole helper type with
>> all its methods to maybe use it for an implicit specialization (and it needs
>> to specialize the helper first to decide whether it even remotely contains
>> suitable methods).
>>
>
> You could do a search for method names and parameters to see if a generic
> helper was a candidate before specialization. That would reduce the possible
> space for needless specializations right? For non-object types this would be
> even less intrusive since it would only be competing with other helper
> methods.
Note: CC’ing Sven in case he’s not getting these.
First off see my reply above about implicit. Question is why can’t you filter
out possible helpers by doing a pre-pass check for matching names? It’s
certainly going to add some compile time overhead but it can be put behind a
mode switch in the case it’s worthwhile (the compile time may be negligible in
many cases). There’s also some optimizations I could think of so I wouldn’t
give up on implicit specialization just yet.
I had a look at some old notes I had on the idea of generic helpers since we
talked about this some years back (for generic arrays) and here's what I found.
2) Right now helpers only support single types but they would need to be
extended to support “array of T”, “set of T”,which by, why aren’t those
supported as it is? I can’t seem to think of any reason they should be
disallowed. The alternative is using an auxiliary generic type which kind of
confounds things because then you’re extending a new type instead of the
underlying array of set type.
3) If there was a generic helper for a generic class it may be too verbose to
use the normal inline specialization syntax ie:
generic THelper<T> = class helper for specialize TMyClass<T>
So I wonder if the shorthand:
generic THelper<T> = class helper for TMyClass
Could be used, providing the type to be extended has a matching generic
parameter list. At the very least the “specialize” sounds wrong when reading it.
Regards,
Ryan Joseph
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