Re: C23 thoughts and opinions

On 23/05/2024 22:23, Kaz Kylheku wrote:

On 2024-05-23, David Brown <david.brown@hesbynett.no> wrote:

So yes, I /could/ use enum constants for things that are not
enumerations.  I /did/ use them for that.  But going forward with C23,
I'll use constexpr instead.

 The value of an enum is:
 1. Compiler warns of incomplete switch cases.

(gcc -Wswitch or -Wswitch-enum)
To be clear - I will, without doubt, continue to use "enum" for enumerations and enumerated types.  For enumerations, enum gives all the advantages you mention and more (such as automatic choice of values).
But I'd rather use "constexpr" for constant expressions that are not enumerations.

 2. In a debugger when you examine an enum-valued expression or
    variable, you get the symbolic name:
 3. Safety (with C++ enum rules: no implicit
    conversion from ordinary integer type to enum).

(gcc -Wenum-compare -Wenum-conversion -Wenum-int-mismatch)

 Historically, C code bases have abused enums to defined constants
like "enum { bufsize = 1024 }" for understandable reasons, but it is a
cringe-inducing hack, which is also incomplete and inflexible; e.g. what
if we want a floating-point constant.
 I've benefited from (3) in C programs that were contrived
to be compilable as C++. (That practice, though, tends to increasingly
hamper your dialect choice though, as the languages diverge and make
only small steps here and there to become closer.)