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Comment by iamrohitbanga | Hacker News Reader

I feel where Ruby's optional parenthesis syntax really shines is in method call chaining.

e.g.

    employees.flat_map(&:addresses).map(&:city).uniq.sort
    # in place of
    employees().flat_map(&:addresses).map(&:city).uniq().sort()

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Oh thank god, we saved ourselves six characters! And the only thing we sacrificed is knowing for sure whether we're accessing an object's property, or calling a method!

It's all methods in Ruby. Properties are private. You access them via methods.

As a non-Ruby programmer, this sounds like it makes it non-obvious whether you're calling a class' method or attribute. Do you end up relying on your editor to help you out ?

It's actually nice that it does not matter if it's a function or attribute that your calling in ruby. Check out the Uniform access principle (https://en.wikipedia.org/wiki/Uniform_access_principle).

When used correctly you can write IMHO really clean and concise OOP code where (cascading) changes are easily made.

Where this kills me is ambiguous commas.

    something = [ alpha beta, gamma ]

I have no idea if I just invoked alpha(beta, gamma) and put the result into a single-member array, or if I've got an array with two elements - alpha(beta) and gamma.

It's not actually ambiguous; though it is a bit of language-specific syntax to learn.

Agreed. It is the "idiomatic" way of writing code in Ruby. I love Java but writing lambda expressions in Java with deeply nested parenthesis makes the code really ugly and less readable esp with chaining.

As far as I understand, Ruby style is writing the code in the most elegant way to increase readability and (hopefully) reduce chances of bugs.

So what would you expect my example above do, at a glance?

Or is my example something that a good Ruby developer never write at all?

It's not ambiguous to the computer, but it is ambiguous to a human at a glance.

Yep you can create ambiguous nasty code like this. It's is clearly not expressing intent, so you would add parentheses.

> As a non-Ruby programmer, this sounds like it makes it non-obvious whether you're calling a class' method or attribute.

“Attributes” in Ruby are just methods that do attribute-like things, so there is no ambiguity: it is always a method.

Every langauge with native support for property setters and getters has the same problem. C# has decent IDE support, in JS we pretend it never happens, Ruby is at least upfront

As someone who writes basically only C++ and Python, that code looks like a nightmare.

Python has the `@property` decorator, which effectively disguises method calls as attribute access. To me, that's as bad, if not worse, than the ruby code posted above.

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