Regex to match every occurence of a character except the first one

I’m trying to figure out a regex that will match a = after the last occurrence of a closing bracket.

So in those examples, it should match :

=FUNCTION(LABEL="TEST")=
                       ^ this

=FUNCTION(LABEL="TEST")===
                       ^^^ this

How can I write a regex that follows this requirement?

>Solution :

Use a lookahead:

=(?=[^)]*$)

…in which = matches a =, and [^)]*$ ensures that there are no closing bracket following it until the end of string.

Try it on regex101.com.

Try it:

console.config({ maximize: true });

console.log('=FUNCTION(LABEL="TEST")='.match(/=(?=[^)]*$)/));

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