This is one area where C-style for-loops would have provided a clean
solution (combining multiple conditions with &&), but once they're removed
any extra conditions will have to move inside the loop.
Pros:
- It's a simple way to express a common piece of control flow that
otherwise requires negation and another set of braces.
- Its meaning is easy to understand.
Cons:
- It's a new feature.
- Naming might cause confusion with while-loops.
Open questions:
- How/could it be combined with "where" clauses? Would order matter?
- Does anyone else care?
My 2c: it is adding complexity and potential for confusion for very little gain. Also, “where” and “while” are structurally different, because while isn’t a modifier that occurs in many other places. Adding “where” to for loops was justified by a push to improve pattern matching in swift.
-Chris
···
On Dec 31, 2015, at 12:42 AM, Jacob Bandes-Storch via swift-evolution <swift-evolution@swift.org> wrote:
Currently, for-loops admit a "where" clause:
for x in seq where cond {
...
}
behaves like
for x in seq {
if !cond { continue }
...
}
I'd be interested in a "while" clause:
for x in seq while cond {
...
}
would behave like
for x in seq {
if !cond { break }
...
}
This is one area where C-style for-loops would have provided a clean solution (combining multiple conditions with &&), but once they're removed any extra conditions will have to move inside the loop.
Pros:
- It's a simple way to express a common piece of control flow that otherwise requires negation and another set of braces.
- Its meaning is easy to understand.
Cons:
- It's a new feature.
- Naming might cause confusion with while-loops.
Open questions:
- How/could it be combined with "where" clauses? Would order matter?
- Does anyone else care?