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Comment by rdfi | Hacker News Reader

Instead of booleans or enums why not have different methods for each value of the bool/enum, e.g.: openAsync(...), open(...)

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I've seen this in practice a lot in jQuery and many people with jQuery experience. You end up with methods like showFoo / hideFoo, enableFoo / disableFoo, and then you have to continuously write if-statements like this:

    if (someCondition) {
        showFoo();
    } else {
        hideFoo();
    }

Instead of:

    setFooVisible(someCondition);

The point being, creating lots of different methods for each variant reduces one's ability to use other abstraction tools, like variables, to control parameters.

Functions are first-class values, so what's wrong with:

    (someCondition? showFoo : hideFoo)();

You can also pass in arguments if they both accept the same parameters, eg.

    (someCondition? show : hide)(foo, duration);

Except they're methods so you have to write

    (someCondition ? foo.show : foo.hide)();

except the language does not auto-bind so you have to write

    (someCondition ? foo.show : foo.hide).call(foo);

or maybe

    (someCondition ? foo.show.bind(foo) : foo.hide.bind(foo))();

Or:

    foo[someCondition? 'show' : 'hide']();

Although looking up functions using raw strings is less than elegant. I'd be tempted to abstract the pattern using a function, but at that point I'd be doing functional programming anyway and wouldn't be using methods ;)

> I've seen this in practice a lot in jQuery and many people with jQuery experience.

A bit odd given jQuery often provides both options e.g. show[0]/hide[1] and toggle(bool)[2].

[0] http://api.jquery.com/show/

[1] http://api.jquery.com/hide/

[2] http://api.jquery.com/toggle/#toggle-display

Yes (and toggleClass too), but they were only added in 1.3.

Different names don't scale well beyond a single boolean argument.

Instead of having different methods like open/openAsync why not have enums?

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