Simple RegEx error

[Micromegas]

I can't believe I'm having a problem with this very simple RegExMatch() call:

Code: Select all

#NoEnv
#SingleInstance force
#Warn

sHaystack := "abcyxw"
iMatch := RegExMatch(sHaystack, "^(?P<Begin>.+)y", Match)		
if iMatch
	sMatch := MatchBegin
else
	sMatch  := "(nothing)"
MsgBox % "iMatch=" iMatch "`nsMatch=""" sMatch """"

This gives the following warning: Warning: This variable has not been assigned a value.
Specifically: MatchBegin (a global variable)
---> 008: sMatch := MatchBegin

and the message box says:iMatch=1
sMatch=""- instead of saying iMatch=1
sMatch="abc".

I tried using the other allowed syntax constructs, such as Mode 3 or numbered rather than named subpatterns, but to no avail. What am I missing?

[RussF]

I'm not fluent with regex, but I can tell immediately from your warning message, as you should be able to, that you are trying to get data from the undefined variable MatchBegin when the output variable from your RegExMatch function is Match.

Russ

[Micromegas]

Sorry, my bad: I had a non-printable character before the variable name. (I remember having the same problem two years ago, when someone here pointed it out.)