> I get this
>
> var i:Int = 0
> for i in (0..<len)
> {
> //do something
> }
>
> ....
>
> for i in (0..<len)
> {
> if something is true
> {
> break
> }
> }
>
> use i ??
> What is i now :) !!!!
Yes and it is extremly confusing sintax..... and you may create such bug
without even notice just by changing the old C style for cycles.
I am still new to SWIFT (2 months). Here is what I thing
1. Breaking existing code meens that swift is still in beta and one should
always think twice before investing in big project.
2. swift has no clear vision of "for" cycles. All cycles resemble "while" cycle
when compiled to CPU instructions and can be implemented with while loop.
Pascal had a limited for cycles just for easy enumeration. C on the other hand
has much more capable for cycles that suited many cases. From what I read there
is no clear idea about "for" in swift. They have to write down the scenarios
they want to cover and and offer ONE syntax for them all. Having a different
syntax for different C scenarios is confusing - better leave the C syntax.
3. swift has hidden function calls like C# - that affects the code performance
in an unexpected way. Function calls are expensive in ARM architecture and they
should be avoided in loops. So this leads to the arrays. Swift is slow beacause
reading and changing array members is slow and that is what usually is made in
loops. There should be no hiden function calls there. I may suggest using
UnsafeMuttablePointer to create a new fast array class or struct and add it
into the language for everyone to use.
4. writing many things in one line is BAD in million lines projects. It is
called "compressed logic" - leads to bugs, and slow code maintenance. Swift
closers are becoming really messy at this point so some rules against
compressed logic are needed.
5. There are many great things in swift that I have not seen anywhere else like
swift functions, interaction with C code, dictionaries and more and more. So I
have a strong believe in the swift development team .
On Thursday, March 24, 2016 5:59 AM, Brent Royal-Gordon
<[email protected]> wrote:
> I get this
>
> var i:Int = 0
> for i in (0..<len)
> {
> //do something
> }
>
> ....
>
> for i in (0..<len)
> {
> if something is true
> {
> break
> }
> }
>
> use i ??
> What is i now :) !!!!
The outer `i` is 0 because it was never used. The expression `for i in...`
implicitly declares a new `i`.
--
Brent Royal-Gordon
Architechies
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