Question

well i am currently writing a script that is meant to check the logs of another script i wrote to see if it has had three or more unsuccessful pings in a row before a successful one, this is just barebones at the moment but it should look something like this

fileread,x,C:\Users\Michael\Desktop\ping.txt
result:=RegExMatch(%x% ,failure success)
msgbox,,, The file is = %x% `n the result is  = %result%

now the file that is trying to read is

success failure success

and for some reason, when it reads the file it says that the variable %x% ‘contains illegal characters

• when i copy and paste the contents of ping.txt into the script and save it as a variable it works
• i have made sure that the file has windows line endings CR +LF
• i have assigned the variable generated in file read as another variable thus stripping any trailing or leading whitespace characters
• the file is encoded in ANSI and still has the problem with UTF8

Answer 1

Function parameters take variable names without the % symbol, simply remove them.

I also want to point out that if the second parameter is meant to be a regular expression,
instead of a variable containing a regular expression, you will need quotes around it.
As is your script passes an empty string as the pattern which will always return 1
(failure is interpreted as a variable with an empty string associated with it.).
To quote Lexikos:

“An empty string, when compiled as a regex pattern, will match exactly
zero characters at whatever position you attempt to match it. Think of
it this way: For any position n in any string, the next 0 characters
are always the same.”

Because you are simply truth testing,
or finding the index I want to point out that Autohotkey has a useful shorthand operator for this.

string := "this is a test"

f1::
result := RegExMatch(string, "\sis")
traytip,, %result%
Return

f2::
result := string ~= "\sis"
traytip,, % result
Return

These hotkeys both do the same thing; the second uses the shorthand operator ~=
and notice how the traytip parameter in the second example has only one %

When you start a command parameter with a % that starts an expression,
and within an expression variables are not enclosed with %.

The ternary operator ?: is also very useful:

string := "this is a test"
f3::traytip,, % (result := string ~= "\sis") ? (result) : ("nothing")

It might look complicated but it’s very simple.
Think of
% as if
? as then
: as else
If (true) then (a) else (b)
% (true) ? (a) : (b)

A variable will be evaluated as False if 0 (or nothing) is assigned to it.
But in this example “\sis” is matched and the index of the space is returned (5),
so it is evaluated as True.

You can read more about variables and operators here:
http://l.autohotkey.net/docs/Variables.htm