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klochner

tldr: && has higher operator precedence than "and"

Significantly, "&&" > "=" > "and", which can lead to unintended results when refactoring "&&" --> "and"

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I.E.: why you should always use && instead of "and".

So why have both?

You guys would benefit from reading the article.

Read the article.

I did. And I still don't see why you'd have both.

It seems like a landmine for someone learning the language and a place for bugs to creep in to code.

Pick one and go with it. The extra expressiveness or whatever a ruby person would call it, that comes from the alternate forms just doesn't seem worth it.

> Pick one and go with it.

They did. It's `&&` and `||`.

I understand your point when it comes to it being a potential landmine, and honestly I never use them myself. But I've never seen any ruby guides or docs use `and` instead of `&&`, and I have seen skilled rubyists make great (and correct) use of `and`.

> They did. It's `&&` and `||`.

I assume you mean idiomatically chosen, since clearly the decision wasn't made at the language level.

> I have seen skilled rubyists make great (and correct) use of `and`.

I'm obviously not a ruby programmer, so it doesn't matter much to me, but it seems odd to argue that having a largely disused second set of logical operators in a language that skilled people periodically trot out for some cases is anything but a design wart. Maybe it's a cultural thing in the ruby world.

And, honestly, I don't mean that to sound snide or slighting. It's just odd to me.

Fair point. It is a bit odd. IIUC the low/reverse-precedence operators came from Perl, and whether or not to use them is just a stylistic choice. It's clear what this means:

> raise "ooops" unless do_something()

But even so, it reads a bit backwards. Some codebases do this instead:

> do_something() or raise "oops"

That's just repeating one of the examples in the article, but it jumps out to me as the one I've seen most often.

I never understood what Perl (and now Ruby) has against if statements.

  foo or do_something()

is exactly the same as

  if foo {
      do_something()
  }

Except the latter is WAY less likely to be accidentally misread.... and don't even get me started on

  do_something() unless foo

It's all just a matter of taste and preference. If you find yourself consistently misreading commonplace ruby, maybe ruby isn't for you.

To avoid a potentially useful language feature because you might make a mistake with it is, to me, a absurd.

A much better argument might be Use <feature> only when you fully grasp its use, which is true of any feature. Some are more difficult to understand than others, especially when trying to relate a feature to another language, but that's just not an argument I can support.

It might not just be you working. Sure, use things that you understand. The problem comes when you aren't even aware you don't understand due to subtleties you may have not encountered yet. Then you do some debugging, do some googling, and bam, now it's "obvious to anyone with half a brain, everyone should just RTFM"

I understand the potential harm when working with teams, but I also recognize that it's a shame to limit your use of the language to avoid potential trouble. Surely there's some middle ground to be found over dogma such as Never use <feature>.

I'm not suggesting that everyone should understand every detail of every potentially misunderstood feature. I'm suggesting that these situations should be dealt with on a case-by-case basis.

No. You should use them appropriately.

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