Re: Is there a way to do large block of source code comments

[gautier_niouzes@hotmail.com]

Le mercredi 3 septembre 2014 20:53:01 UTC+2, Adam Beneschan a écrit :

> I don't see why not.  The language designers would have to come up with some simple rules, but this isn't hard:
> 
> The sequence (*, if not in a conventional comment, starts a block comment.  The comment ends with the next occurrence of the sequence *) that is not in a conventional comment.  Within a block comment, it is illegal for the sequence (* to appear except in a conventional comment.  A character sequence is "in a conventional comment" if it occurs anywhere between the sequence -- and the nearest subsequent end-of-line character. 

Hey, not so easy! If you admit (* in a conventional comment within a block comment, then you need to specify that a *) is closing the nested (*, or perhaps not (then it would be closing the outer block comment), and also what happens if a *) is in a conventional comment but a one or more rows later. Is it closing the nested (* or the outer one ? Of course the question goes recursively with nesting...

I have some memories of headaches in the 80's or 90's when I was programming in Pascal with *) closing a {, or not, and so on. And I'm happy not having to deal with these block comments since then.

These block comments become very quickly very messy, especially because there may be unforeseen cases in the specification ( :-) ), and even if the specification is bullet-proof, compilers, parsers, editors or pretty printers may easily misinterpret the rules...
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