[Issue 5714] case ranges in final switches

May 22, 2018

Dmitry Olshansky

Aug 09, 2020

Walter Bright

Dec 17, 2022

Iain Buclaw

Jan 21, 2023

Nick Treleaven

Jul 02

Bolpat

https://issues.dlang.org/show_bug.cgi?id=5714 Dmitry Olshansky <dmitry.olsh@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |bootcamp CC| |dmitry.olsh@gmail.com --

https://issues.dlang.org/show_bug.cgi?id=5714 Walter Bright <bugzilla@digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- See Also| |https://issues.dlang.org/sh | |ow_bug.cgi?id=5713 --

https://issues.dlang.org/show_bug.cgi?id=5714 Iain Buclaw <ibuclaw@gdcproject.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P2 |P4 --

https://issues.dlang.org/show_bug.cgi?id=5714 Nick Treleaven <nick@geany.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |nick@geany.org --- Comment #4 from Nick Treleaven <nick@geany.org> --- (In reply to Andrej Mitrovic from comment #1) > And it also limits the number of cases to 256 (for optimization purposes?). > > So a final switch would only work on byte-types. See issue 15279 which seems to be an implementation issue rather than a design decision (the pull comment suggests lowering case range statements to an if/else instead). --

July 02

[Issue 5714] case ranges in final switches

Posted by Bolpat

Permalink

Bolpat

Permalink

https://issues.dlang.org/show_bug.cgi?id=5714

Bolpat <qs.il.paperinik@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |qs.il.paperinik@gmail.com

--- Comment #5 from Bolpat <qs.il.paperinik@gmail.com> ---
The limitation of the number of `case` labels is entirely orthogonal to allowing case ranges for `final switch`, as the ranges are just syntactic sugar for writing them out.

This errors:
---
void main()
{
    ubyte u;
    final switch (u)
    {
        case   0: .. case 100: break;
        case 101: .. case 255: break;
    }
}
---

This is fine:
---
void main() {
    ubyte u;
    Lswitch: final switch (u)
    {
        static foreach (i; 0 .. 100 + 1)
        {
            case i: break Lswitch;
        }
        static foreach (i; 101 .. 255 + 1)
        {
            case i: break Lswitch;
        }
    }
}
---

The error makes no sense. It might have made sense in 2011, but in 2024, it just requires some boilerplate to work.

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