http://www.*-*-*.com/

I find positive and negative lookahead search and I didn't see this in
grep
(well i'm a newbie in windows programming :) )
negative lookahead search is so sensitive but I can't understand
positive lookahead search because I think it's just same with normal
search

in above URL (?=pattern) explains
------------------------------------------------------------------------------
Positive lookahead matches the search string at any point where a
string       matching pattern begins. This is a non-capturing match,
that is, the match is not captured for possible later use. For example
'Windows (?=95|98|NT|2000)' matches "Windows" in "Windows 2000" but
not "Windows" in "Windows 3.1". Lookaheads do not consume characters,
that is, after a match occurs, the search for the next match begins
immediately following the last match, not after the characters that
comprised the lookahead.
-------------------------------------------------------------------------------

But I can't find difference between normal search and positive
lookahead search
for example there's sentences like "windows98 is here" and
"windows2000 is there"
then normal search windows(98|2000) will match both sentences
and positive lookahead search windows(?=98|2000) also match both
sentences
Well, I think I'm misunderstanding the meaning of positive lookahead
search :)
plz show me some example or explanation

have a nice day :)

The second pattern can not match anything.

Csaba

win98 = "windows98 is here"
win2k = "windows2000 is there"

with new regexp

  'match the string "windows98" or "windows2000"
  .pattern = "windows(98|2000)"
  wscript.echo .execute(win98)(0)    ' windows98
  wscript.echo .execute(win2k)(0)    ' windows2000

  'match the string "windows", but only if it's followed by "98" or "2000"
  .pattern = "windows(?=98|2000)"
  wscript.echo .execute(win98)(0)    ' windows
  wscript.echo .execute(win2k)(0)    ' windows

end with

--
Steve

Washing one's hands of the conflict between the powerful and the powerless
means to side with the powerful, not to be neutral. -Paulo Freire