Replace multiple occurrences in the same line - regex

Question

I'm using Notepad++ to replace some lines. Basically what I want to do is:
line 1 -
STR::P=FOOXPATTERN=5 AND MORETHINGS YPATTERN=9 BUT XPATTERN=3 AND YPATTERN=20
line 2 -
MOR::P=BAR XPATTERN=1 STRSTR MORETHINGS YPATTERN=1BUT XPATTERN=10 AND YPATTERN=40
...
So this must be transformed in:
line 1
XPATTERN=5|YPATTERN=9|PATTERN=3|YPATTERN=20
line 2 -
XPATTERN=1|YPATTERN=1|XPATTERN=10|YPATTERN=40
My point is that I can have many XPATTERN and many YPATTERN in the same line. Then I would like to replace all my line for the pattern found.
I tried to use negation on regex, but with no success.

Answer 1

Ctrl+H
Find what: (?:^|\G(?!^)).*?((?:XPATTERN|YPATTERN)=\d+)(?:(?!(?:XPATTERN|YPATTERN)=).)*($)?
Replace with: $1(?2:|))
CHECK Match case
CHECK Wrap around
CHECK Regular expression
UNCHECK . matches newline
Replace all
Explanation:
(?: # non capture group
^ # beginning of line
| # OR
\G(?!^) # restart from last match position, not at the beginning of line
) # end group
.*? # 0 or more any character but newline
( # group 1
(?: # non capture group
XPATTERN # XPATTERN
| # OR
YPATTERN # YPATTERN
) # end group
=\d+ # equal sign followed by 1 or more digits
) # end group 1
(?: # non capture group
(?! # negative lookahead, make sure we haven't after:
(?: # non capture group
XPATTERN # XPATTERN
| # OR
YPATTERN # YPATTERN
) # end group
= # equal sign
) # end lookahead
. # any character but newline
)* # end group, may appear 0 or more times
($)? # group 1, end of line, optional
Replacement:
$1 # content of group 1 (i.e. X or Y PATTERN = digits)
(?2 # IF group 2 exists (end of line), do nothing
: # ELSE
| # add a pipe character
) # ENDIF
Screen capture (before):
Screen capture (after):

Answer 2

Use a regexp that matches the pattern and anything before it, and replaces it with just the pattern.
Replace: .*?((XPATTERN|YPATTERN|ZPATTERN|...)=\d+)
With: |\1
If there's something after all the patterns, you can remove the rest after the above replacements with:
Replace: ^((\|(XPATTERN|YPATTERN|ZPATTERN|...)=\d+)*).*
With: \1
This will leave a | at the beginning of each line. You can remove that as a third step:
Replace: ^\|
With: empty string