RE: [PHP] ereg_replace()

Oh my god. I feel dumb. Thanks guys. --Drew Vogel On Wed, 6 Sep 2000, Lars Torben Wilson wrote: > > I believe Nick is correct. > > Drew P. Vogel writes: > > If the filter() function is being called first, with the arguments > > interprected first, then how does it return "L"? The only way the $flags > > It's not returning "L". It's returning "\2". This then appears as > the > second argument to eregi_replace() (as a string); it is not until after > this has occurred that eregi_replace() parses the \2 into an 'L'. Like > this: > > Step 1: > $templateLine = eregi_replace($matchRegex, filter("\\2", "\\1"), > $templateLine); > > At this point, filter() is called first, as noted > before. Therefore, the arguments to filter() are "\\2" and "\\1", > since the reference replacement hasn't occurred yet. This is why > echoing $flags in filter() gives '\2'. > > Step 2: > filter() has returned the value of $flags, '\2', leaving the line > above looking like this to the parser: > > $templateLine = eregi_replace($matchRegex, '\2', $templateLine); > > eregi_replace() now executes, and the '\2' is replaced by the second > parenthesized substring of the match: 'L'. > > ...and there you go. It may be a good idea to rework the logic to > avoid these little subtleties; Nick gave one example; this would be > another: > > while (eregi($matchRegex, $templateLine, $matches)) { > $replace_text = filter($matches[2], $matches[1]); > $templateLine = eregi_replace($matchRegex, $replace_text, $templateLine); > } > > > > argument to filter() could hold the value of "L" to be returned is if > > ereg_replace() passed it as the second parenthesised token. The script is > > meant to replace the text between [L and ] with a corresponding > > value. This is why it is supposed to return "L" with 'return $flags;'. > > > > --Drew Vogel > > > > On Thu, 7 Sep 2000, WILSON, Nick wrote: > > > > > It's not a bug, it's the way you are using ereg_replace. The second > > > argument is the replacement text (or reg exp). So in your case, the > > > filter function is first called with arguments \1 and \2 (the first > > > \ will be an escape character). > > > > > > To do what you want to do, you will have to assign the matched text > > > to variables and then call filter, ie something like > > > > > > $templateLine = eregi_replace( $matchRegex, "\\1:\\2", $templateLine ); > > > list($phase, $flag) = split (":", $templateLine); > > > filter("phase", "$flag" ); > > > Hope this helps, > > Torben > > -- > +----------------------------------------------------------------+ > |Torben Wilson <torben@php.net> Netmill iTech| > |http://www.coastnet.com/~torben > http://www.netmill.fi| > |Ph: 1 250 383-9735 torben@netmill.fi| > +----------------------------------------------------------------+ >