It's extremely common in reflection based code to generate declarations using mixin, and possibly in order of 80% of the time, those declarations have generated names.
Since string mixin's must contain whole declarations, it's impossible to supply a generated function name without writing the entire body of the declaration inside of a string. This is really ugly and difficult to maintain.
Function bodies written in strings lose:
Syntax highlighting
Auto-completion
Step debugging
Hover tooltip inspection
Text mixins are really unenjoyable and I'm very tired of it, particularly when I have huge declaration that are only text because of the name.
I suggest to add `pragma(identifier, StringExp)` which may appear anywhere that an identifier may appear.
In my code, I expect this will reduce instances of string mixin by something close to 90%, and that creates much more reasonable, readable, and maintainable code, and the IDE can keep working like it's meant to.
For example:
string makeIdent(size_t n) { return "name" ~ n.to!string; }
template T(size_t N)
{
void pragma(identifier, makeIdent(N))(Args...)(Args args)
{
...
}
}
Also useful in places where an entire expression would have had to be enclosed in text, like:
int pragma(identifier, getName()) = expression + 1 * myThing.members[n].x;
Comment #1 by dfj1esp02 — 2019-07-25T08:36:28Z
If you need only a name, you can just generate an alias:
mixin(q{ alias generatedName=staticName; });
Or forwarding:
mixin(q{ void generatedName(){ staticName(); } });
void staticName()
{
//code here
}
Comment #2 by turkeyman — 2019-07-25T17:00:20Z
It's possible that I might have thought of that... ;)
Comment #3 by gooberman — 2019-07-27T13:02:58Z
100% for this. There's a large chunk of code I can simplify by just defining things inline instead of having to provide extra workarounds like noted in all of the above posts.
Being able to arbitrarily override a symbol's identifier is going to have applications well outside of just this use case.
Comment #4 by destructionator — 2019-08-05T00:59:50Z
I'd actually prefer the syntax just to be mixin. Change the grammar so declaration names can be replaced with mixin(x) and the mixin must return an identifier as a string.
But regardless, yes, this would basically finish `static foreach` imo.
Comment #5 by turkeyman — 2019-08-05T07:06:38Z
mixin would be fine in that context... but it might look a little bit weird?
Comment #6 by robert.schadek — 2024-12-13T19:04:41Z