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Discussion on: Ternary Unwrapping in Swift

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aidantwoods profile image
Aidan Woods •

Of course you can put arbitrary functions in either, so in general this operator will be useful – but when both code paths differ only in data you can reduce to a nil-coalescing though. E.g. the initial example can be written as ;-)

let foo = Foo(optionalDependency ?? fallback)
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aidantwoods profile image
Aidan Woods •

Just in an attempt at playing code golf, the int example could also be written as

let sentence = optionalNumber.map { "My favorite number is \($0)" }
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Though, of course again it's specific to the second code path happening to be convenient – in general the operator will remain more useful.

One could write

let sentence = optionalNumber.map { "My favorite number is \($0)" } ?? fallback()
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But I think that fails in the direction of

improve[ing] the readability of the code

So your solution wins here ;-)

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danielinoa profile image
Daniel Inoa •

Ultimately, it's a matter of taste.
The ?? | operator, however, allows me express the same idea in the style of an operator (ternary conditional) that's already common in many programming languages.

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eric_summers_0b8bd15160d8 profile image
Eric Summers •

Using map in this way is documented for this use in the standard library, so I prefer that method.