Convert deeply nested if/else to do/while(false) with breaks for parseAttribute

[hoelzro]

01d3cde refactored parseMacroParameterAsAttribute to use a do/while(false) construct with break statements - this updates parseAttribute with an analogous refactoring for consistency

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[linonetwo]

what does do while (false) mean here? could it be a function return instead?

[hoelzro]

@linonetwo do { ... } while(false) just means the "loop" will run exactly once - so it's not really a loop at all! This is definitely a little weird, but it's for the sake of the break statements.

A function return could be used - but if we did that, the other code at the end of the function body would get missed. And while we could wrap this in an immediately-executed function literal, like this:

(function() {
  if(cond) {
    ...
    return;
  }
  ...
})();

...I feared the overhead of creating and calling those function objects might meaningfully impact performance, hence the do/while(false).

[saqimtiaz]

@hoelzro could you please resolve the conflicts? We can now merge this for v5.5.0.

[hoelzro]

@saqimtiaz Should be all set now!

[saqimtiaz]

Thank you @hoelzro