3 ms·

This all looks good to me until I'm unwrapping an optional and checking it's length in Swift, which normally looks like: guard let array = obj.someArray,

This all looks good to me until I'm unwrapping an optional and checking it's length in Swift, which normally looks like: guard let array = obj.someArray, array.count > 0 else { throw SomeError }

pantalaimon 8y ago
`array.count < 1` still sounds reasonable though.
- zapzupnz 8y ago
  Only if I _want_ the array to be empty, otherwise I have to put an ! in front of the that — which in Swift also needs brackets — which is just adding noise to the signal, really, which really defeats the purpose of avoiding the greater than symbol here.
saagarjha 8y ago
A somewhat stupid way to solve this issue (of what is likely poorly-designed API, given what you're trying to do here; optional Arrays are generally a code smell) is to abuse the nil coalescing operator: guard !(obj.someArray?.isEmpty ?? true)
- zapzupnz 8y ago
  Well sure, except if the array is optional (and I agree it's code smell, but that's what you get when you use other peoples' libraries, I guess) that statement doesn't unwrap the array for me to use; I'll either need to do it manually on a second line (waste of effort) or every time I try accessing that variable. If I access it a lot, this is inefficient duplication. Plus, I don't like abusing the nil coalescing operator. Once you're abusing anything, you're adding signal to noise and making the intent of a statement less clear than necessarily, I feel. +1 for isEmpty, though. According to the docs, count iterates over collections that don't conform to RandomAccessCollection, so best to avoid unnecessary overhead by adopting good practice! Thanks for that.
  - saagarjha 8y ago
    In your specific example, it didn't look like you wanted to use that array, so I thought I could save you a variable. If you are planning to use it, then by all means bind it to a variable for reuse.
    - zapzupnz 8y ago
      What other use is there for a conditional let?
      - saagarjha 8y ago
        I thought your only use for the array was to check its count. Now that I think about it, that was probably a stupid assumption.
deathanatos 8y ago
Why can that not be swapped to: guard let array = obj.someArray, 0 < array.count else { throw SomeError } ?
- zapzupnz 8y ago
  It could be changed to that, but what am I really asking? "Is zero lower than the length of my array" is a bizarre way to word the question, as opposed to "is the length of my array greater than zero". I believe in self-documenting and obvious code, and I think if statements should read as much like a human sentence as possible.

This all looks good to me until I'm unwrapping an optional and checking it's length in Swift, which normally looks like: guard let array = obj.someArray, array.count > 0 else { throw SomeError }

pantalaimon 8y ago

`array.count < 1` still sounds reasonable though.

zapzupnz 8y ago
Only if I _want_ the array to be empty, otherwise I have to put an ! in front of the that — which in Swift also needs brackets — which is just adding noise to the signal, really, which really defeats the purpose of avoiding the greater than symbol here.

saagarjha 8y ago

A somewhat stupid way to solve this issue (of what is likely poorly-designed API, given what you're trying to do here; optional Arrays are generally a code smell) is to abuse the nil coalescing operator: guard !(obj.someArray?.isEmpty ?? true)

zapzupnz 8y ago
Well sure, except if the array is optional (and I agree it's code smell, but that's what you get when you use other peoples' libraries, I guess) that statement doesn't unwrap the array for me to use; I'll either need to do it manually on a second line (waste of effort) or every time I try accessing that variable. If I access it a lot, this is inefficient duplication. Plus, I don't like abusing the nil coalescing operator. Once you're abusing anything, you're adding signal to noise and making the intent of a statement less clear than necessarily, I feel. +1 for isEmpty, though. According to the docs, count iterates over collections that don't conform to RandomAccessCollection, so best to avoid unnecessary overhead by adopting good practice! Thanks for that.
- saagarjha 8y ago
  In your specific example, it didn't look like you wanted to use that array, so I thought I could save you a variable. If you are planning to use it, then by all means bind it to a variable for reuse.
  - zapzupnz 8y ago
    What other use is there for a conditional let?
    - saagarjha 8y ago
      I thought your only use for the array was to check its count. Now that I think about it, that was probably a stupid assumption.

deathanatos 8y ago

Why can that not be swapped to: guard let array = obj.someArray, 0 < array.count else { throw SomeError } ?

zapzupnz 8y ago
It could be changed to that, but what am I really asking? "Is zero lower than the length of my array" is a bizarre way to word the question, as opposed to "is the length of my array greater than zero". I believe in self-documenting and obvious code, and I think if statements should read as much like a human sentence as possible.