Preprocessor macro to quote its argument

[Checkpoint Technologies]

In article <1990Aug21.175138.24633 at zoo.toronto.edu> henry at zoo.toronto.edu (Henry Spencer) writes:
>The right way to fix the notorious `CTRL(D)' problem is to quote the D.
>There is no portable way for the macro to supply the (single) quotes.
>This has been true for a long time; tokenizing preprocessors existed
>well before the ANSI C effort started.

(This is just off the top of my head, so please be gentle...)

Why can't this work?

#define CTRL(ch) ((* #ch) - 64)

It's ANSI only. The single # places it's arg in double quotes, making a
string, and the * returns the first byte of the string.

Now, I know this *could* be a constant expression. In ANSI, should
a compiler treat this as a constant expression, which is allowed in
static initializers etc?
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