SE-0243: Codepoint and Character Literals

[Nevin]

@johnno1962

Greater flexibility would have been my preference but a long discussion about the subtleties of unicode normalisation persuaded the thread it was best to steer clear of being able to represent integers outside the ASCII range (The Option 2 vs. Option 4 debate). We can always relax this constraint later if a killer use-case turns up.

This makes absolutely zero sense to me. A Unicode scalar has exactly one canonical integer value.

No normalization should be involved at all. If the source-file places a single Unicode scalar between two apostrophes, then that is a Unicode scalar literal.

It is a literal representation of a single Unicode scalar. And a single Unicode scalar has exactly one integer value, which can be accessed at runtime through its value property.

There is no ambiguity. If a Unicode scalar literal is used to express an integer value, then the only reasonable interpretation is to use the integer value of the Unicode scalar in the literal.