Comment by BugBrother | Hacker News Reader

Comment by BugBrother | Hacker News Reader

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>> How can you fix [X] without breaking almost all existing [Y] code?

For most cases of X, some form of declaration that is scope bound.

Look at e.g. Perl, it changes quickly in this way, with very good backwards compatibility. [Also see strict mode, of course.]

Edit: That said, new keywords like those let/const/module/extends etc should work fine. Please give me them today.

Edit 2: I have been cursing the lack of multiple returns this week. It is a pain returning a hash/object or an array. That really isn't supported, from browsing the standard? :-(

> Edit 2: I have been cursing the lack of multiple returns this week. It is a pain returning a hash/object or an array.

Why is that?

  let rational = (a, b) => [a, b];
  let [numerator, denominator] = rational(38, 4);
  let reduced = rational(numerator/2, denominator/2);

PS. The above code works in stable Firefox.

>> Why is that?

<Cough> Obviously because I'm blind? :-) Thanks.

There's an unwillingness to introduce too many opt-ins into JS as it quickly leads to ever increasing implementation complexity. Note that Perl is one of the few notable languages to have such sort of opt-ins.

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