How do you replace square brackets "[" "]" in a string with Regex?

[#1]

I know that [ and ] are special characters in regular expressions, but I can't figure the right escape string to be able to treat them as a specific character in a pattern string.  

What I want to do, as an example, is convert "[1 1 1]" to "1 1 1".  

[#2 · Accepted solution]

maybe Regex issue with escaped characters 

You are probably fighting JMP's escaping getting mixed up with regex escaping @paul_vezzetti . 

JMP strings make a special case of \[ and ]\ anywhere in a JMP string to turn off JMP's escaping.

try \!\[ and just use a bare ] . Regex should not need to escape the ] unless it is in a [character class].

regex("[1 2 3]","\!\[(.*)]","\1")

"1 2 3"

\!\ is JMP's escape to make a literal backslash. Regex then sees the \[ and behaves as expected.

Alternatively, you could use the \[ ... ]\ , but it creates worse problems if you actually need ]\ in the regex and seems less clear:

regex("[1 2 3]","\[\[(.*)]]\","\1")

I hope JMP gets a regex-quoted string to solve this double escaping issue.

[#3 · Accepted solution]

For something that simple can't you just use substitute?

a = "[1 1 1]";
b = substitute(a, "[", "", "]", "");
show(b);

"1 1 1"