custom character literal macros?

[stevengj]

I wonder if we want to support character literal macros analogous to custom string macros, e.g. b'x' as a synonym for UInt8('x').

This would be a breaking change because b'x' is currently parsed as b' * x':

julia> b = 3; x = 7
7

julia> b'x'
21

This occurred to me in connection with #26286, e.g. if you want to have custom literals for a new character type. Also, there is a lot of code that prints individual ASCII bytes to an io stream. To do this efficiently while still supporting streams in different encodings, you'd ideally want an ASCIIChar type, and it would be convenient to write this as a'x'. Of course, we could define a custom string literal for this, like a"x", but it would be confusing if that were defined to produce a character.

Not a necessary feature by any means, just wanted to throw it out there since it would be a breaking change.

[JeffBezanson]

I think it's better to use string macros for this than to sacrifice x'y'.

[stevengj]

Okay, I figured it wouldn't be popular.