Negative lookahead Regular Expression

Question

I want to match all strings ending in \".htm\" unless it ends in \"foo.htm\". I\'m generally decent with regular expressions, but negative lookaheads have me stumped. Why

Answer 1

String.prototype.endsWith (ES6)

console.log( /* !(not)endsWith */

    !"foo.html".endsWith("foo.htm"), // true
  !"barfoo.htm".endsWith("foo.htm"), // false (here you go)
     !"foo.htm".endsWith("foo.htm"), // false (here you go)
   !"test.html".endsWith("foo.htm"), // true
    !"test.htm".endsWith("foo.htm")  // true

);