On 2/11/2009 1:21 PM, Stavros Macrakis wrote:
On Wed, Feb 11, 2009 at 12:32 PM, Greg Snow <greg.s...@imail.org> wrote:
...The c-style of /* */ allows both types and you can comment out part of a
line, but it is not simple to match and has its own restrictions. Friedl in
his regular expressions book takes 10 pages to develop a pattern to match these
(and the final pattern is almost 2 full lines of text in the book). And this
is without allowing nesting....
Though there is a real debate about the value of multiline, possibly
nested, comments, the regular expression argument is a red herring.
Lexical analysis of multiline comments is a solved problem (and not a
particularly difficult one!), and matters only to language and editor
implementors. Emacs handles them with no problem.
I agree about that. I think the lack of multiline comments comes from
design considerations rather than implementation ones. They're just
not needed, and having two types of comments would lead to weird
interactions, e.g. is the block comment closed in the lines below?
/*
# */
Duncan Murdoch
-s
PS And to give credit where credit is due (important on this mailing
list), the /* */ syntax was defined by PL/I; C simply implemented an
existing convention and popularized it. :-)
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