javascript - Slow performance if a character present after $ in regex -

javascript - Slow performance if a character present after $ in regex -

var longstr = new array(30000).join("a"); longstr.replace(/(.*?)\s*$d/, "$1");

i have above code trim white space nowadays @ end of string. above code takes lot of time execute (~3sec), character "d" there after $ symbol reason bottleneck, removing "d" resolves issue.

i need know happens if character nowadays after $ symbol.

it doesn't matter nowadays after $ (not escaped literal dollar), since signifies end of line , nothing can there after line ends.

javascript regex performance