i may be misunderstanding your question, but javascript does have a replace()
var string = '@!#$123=%';
var newstring = string.replace('@!#$123=%', 'hi');
edit: (see comments) the 5th edition does seem to have this info in it, although it doesn't show up when i link directly to it. here's the relevant part:
The replace( ) method performs a search-and-replace operation. It takes a regular expression as its first argument and a replacement string as its second argument. It searches the string on which it is called for matches with the specified pattern. If the regular expression has the g flag set, the replace( ) method replaces all matches in the string with the replacement string; otherwise, it replaces only the first match it finds. If the first argument to replace( ) is a string rather than a regular expression, the method searches for that string literally rather than converting it to a regular expression with the RegExp( ) constructor, as search( ) does.