Using replace(), global modifier and escaped chars causing comments

Question

having used the internet before I can work out that replace() only replaces the first instance of what you're looking for in a string.

Looking at this question, this question and this question to name a few I know that you have to use the /x/g if you want to search & replace the whole string for x.

My problem is that I'm searching for two characters that get confusing. The asterisks and slash which trigger comments when either of them are used used too close together.

I haven't ever learnt JavaScript so if this is simple I do apologise but I have tried so many different versions of the below I honestly can't remember them all.

$('#answer').delay(1000).each(function(){
                              $this = $(this);
                              $this.html($this.html().replace(/\*/g, 'x').replace(/\/\/g, '÷'));
                                         });

When used like this .replace('*', 'x').replace('/', '÷') it works fine for just one result.

All help appreciated.

Also, have you checked the console? This code is giving a SyntaxError. — Michał Perłakowski, May 26 '16 at 08:51
but `//` together triggers comments also. When I escape the double the console says I'm missing `/` — Bysander, May 26 '16 at 08:53
Using `/\/\/\/g` says "Invalid regular expression: missing /"... Using `/\/\//g` gets "Unexpected token }" as the rest of the line is commented out past the `//` — Bysander, May 26 '16 at 08:56
Doesn't trigger comment, for sure. It's used a lot by everyone want to escape backslash. Are you sure that it's not a problem of your text editor? — Christian Vincenzo Traina, May 26 '16 at 08:59
OK... OK.. Apologies and thanks to everyone. I was misreading the console as the problem *was* an unexpected `}` but it was actually a separate problem from some code later on that had been (partially) removed. The incorrect regex made me sure that it was that and was driving me mad. — Bysander, May 26 '16 at 09:07

Tadas Paplauskas · Accepted Answer · 2016-05-26T09:04:58.567

This works exactly as you described, so if you're having problems look somewhere else. You just wrote an incorrect regular expression and did not read into the errors :) Regular expressions have to be between / symbols and those do not need escaping under any circumstance.

....replace(/\//g, '÷').replace(/\*/g, 'x');

"5*4/2=10".replace(/\//, '÷').replace(/\*/, 'x');
// returns "5x4÷2=10"

In some cases using new RegExp objects would provide better readibility, but in your case that might be clunky.

"5*4/2=10".replace(new RegExp('/', 'g'), '÷').replace(new RegExp('\\*', 'g'), 'x');

Using replace(), global modifier and escaped chars causing comments

1 Answers1