This one bit me today

[Richard O'Keefe]

In article <1989Oct25.090616.19276 at gdt.bath.ac.uk>, exspes at gdr.bath.ac.uk (P E Smee) writes:
> If contents nest, then you can comment out blocks of your code
> for various trial purposes, without having to worry about what's in the
> block you comment out.

This claim is false, as I pointed out before.  If you comment out code
containing strings containing comment delimiters, you're in trouble.
(Yes, this bit me several times.)

> I've known PL/1 programmers to avoid commenting
> their code because (since PL/1 comments don't nest) it would inhibit this
> handy testing trick.

In that case you have known some PL/I (that's a Roman I not an Arabic 1)
programmers who either were not masters of their language or who were
using an incomplete implementation.  PL/I has preprocessor facilities.
To omit a block of code in PL/I, just put
	%IF '0'B THEN %DO;
	<omitted stuff here>
	%END;
around it.

One more time:  if you have a decent editor, and you have either PL/I-style
/* */ or Pascal-style (* *) comments (but not { } comments), you can comment
out regions and bring them back again WITHOUT needing nested comments as such.
If anyone's interested, I'll post my code for it.