Re: C23 thoughts and opinions

On 15/06/2024 23:39, Lawrence D'Oliveiro wrote:

On Sat, 15 Jun 2024 20:27:41 +0100, bart wrote:
 

The "+" is used for compile-time string/data-string concatenation.)

 Why didn’t you follow the C convention of implicit concatenation, just by
placing literals next to each other?

Why is that better?
I did actually have that, but it wasn't as useful. It could only work at the lexical level with actual string literals, for a start.
As it is now I can do this:
    const x = "abc"
    const y = "def"
    const z = x + y           # "abcdef"
These are named constants with proper scope, which are only resolved in a later pass. It also applies to strings created by an embedded file:
    s := "(" + sinclude("help.txt") + ")"
I can use parentheses and it will still work:
    const cond = ...
    print (cond | "abc" | "def") + "xyz"
It will display 'abcxyz' or 'defxyz' depending on 'cond', which is known at compile-time.
I could choose to implement "*" also ...
(I've just spent 10 minutes doing that)
... so that I can do this, where having proper operators comes in useful:
     "A" + "B" * 5           ABBBBB
     ("A" + "B") * 5         ABABABABAB
Here is a use-case:
     const cols = 80
     println "-" * cols             # output divider line
This in a lower level language where strings are not first class types.
How C does it is a hack that was fine for 1972.