On Wed, 29 May 2002, Jonathan Rosenberg wrote: > -----Original Message----- > > From: Thalis A. Kalfigopoulos [mailto:[EMAIL PROTECTED]] > > Sent: Wednesday, May 29, 2002 10:27 AM > > To: [EMAIL PROTECTED] > > Subject: Re: [PHP] comment followed by ?> fails to parse > > > On Wed, 29 May 2002, Jason Wong wrote: > > > > Yes this hightlights another shortcoming of PHP in > > > that it cannot have nested multi-line comments. > > > This is not a shortcoming. This is an issue of the > > scanner of the compiler. It is not possible to > > remember the nesting level of the comments because of > > the nature of regular expressions: they lack memory. > > You need to brush up on your parsing theory. If the PHP parser > can balance parentheses, it can balance comments, also.
>From what I remember from my compilers theory, "regexpr" is one thing, but "grammar" >is another. The parsing phase uses a grammar which is more powerful (every regexpr >has equivalent grammar but not the other way around). But the comments are usually >detected and dropped thereof in the scanning phase (prior to parsing). Of course you >could keep comments around and do the "balanced parenthesis matching" in the parsing >phase. Any fallacies in my memory recollection? cheers, thalis -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
