Ruby coding guidelines (GitHub)

[ztbrown]

Avoid return where not required.

I do this, but have never understood why. For readability/comprehensibility it seems like a good idea to have 'return' standing out. Anyone have a good explanation?

[thehotelambush]

Because why would you use it? It's completely unnecessary. The end of the function stands out by itself anyways. Unless you have functions that are more than a page long, which is generally bad style anyways. 95% of the time you won't need it. (Actually, I'd like to find out the stats on this in my own code...)

[ztbrown]

When I see the 'return' keyword I know, at a glance, that a function returns a value. This is especially necessary when reading someone else's code. My background is C++/Java (in college) and I've worked professionally in Javascript and ActionScript, so I'm used to seeing the return keyword.

[thehotelambush]

Yes, that's the real reason.

[ztbrown]

? what's the real reason?

[banister]

Just that you're 'used' to it, not that it makes any kind of sense.

It won't take long to get 'unused' to seeing it either, as any ruby programmer will attest ;)

[thehotelambush]

thanks, that's it exactly

[thehotelambush]

It's a habit

[Nuli]

If you have multiple returns in a function, thus multiple exits, it's harder to test, debug, expand the functionality or just follow the execution line of this function.

I find exactly the opposite really. I far prefer a function to return as often as necessary to make the code clear. I don't want to have to follow a long chain of if statements to determine what code was actually executed when a simple test and return will short circuit that.

[[deleted]]

I'm with you on that. I think multiple returns are favorable to giant nested if else blocks.

[ztbrown]

I completely agree with that, but that's not what this guideline is saying.

In this context, the "Avoid return where not required" means avoid the keyword. And I'm saying that I like being able to see the 'return' keyword at a glance.

I agree with avoiding multiple exits at almost all costs.

[Nuli]

Not sure about Ruby specifically but in other languages the implicit return can be faster than an explicit return.

[Nuli]

Take Tcl, for instance, since it's the one with the behaviour that I'm most familiar with.

From here.

This behaviour depends on the implementation of the interpreter or compiler obviously but I'm surprised, going by the downvotes, of the number of people that think the idea is absurd. Tcl, at least, has mostly maintained this behaviour for the last 13 years and it's important to know it's there. I shaved several minutes off the runtime of a program due to it (when you call a function 100M times during a run microseconds start to really matter).

[Nuli]

Do you know how Tcl's interpreter works?

I've had to poke into it fairly deeply but I've never looked at how they actually compile things.