> Le 10 juin 2016 à 02:25, Xiaodi Wu <[email protected]> a écrit :
>
> * The word "where" does not consistently imply `break` or `continue`. In
> current Swift, `where` implies `break` in the context of a `while` loop and
> `continue` in the context of a `for` loop. Some users intuitively guess the
> correct meaning in each context, while others guess the wrong meaning.
> Therefore, the only way to learn for sure what `where` means in any context
> is to read the rulebook. That, by definition, means that this is unintuitive.
An example here would have help... I had trouble visualizing the 'where' with
'while'. A quick example I was able to conjure is:
var array = [9,8,7,6,5,4,3,2,1]
while let x = are.popLast() where x < 5 { print(x) }
print(array)
What? 'array' is not empty at the end. I admit, I was surprised by the result
at first. The confusion here is not that 'where' in 'for' behave like
'continue' and 'where' in 'while' act like a 'break', as the later doesn't
conceptually exist. The later concept is using 'where' as a conditional binding
in a 'while' causes a failure of the bind and thus a 'break' out of the loop.
With the acceptance of the revised SE-0099, the 'while' can no longer appear to
be using 'where', thus removing this confusion.
Dany
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