I think `when` would be pretty confusing. If I didn’t know what it meant and I had to guess, I’d probably think that it means what `where` currently means.
Calling it `while` could perhaps cause confusing with the while loop, but it means the same thing in both contexts so people might already feel familiar with it. > > On Jun 7, 2016, at 1:16 PM, Tim Vermeulen via > > swift-evolution<swift-evolution@swift.org(mailto:swift-evolution@swift.org)>wrote: > > > The meaning of the proposed while is not at all a pair for where, since > > > where clauses in while loops would do the same thing as while clauses in > > > for loops. That's crazy. > > > > It sounds crazy, but it’s the nature of the while loop. A where clause in a > > while loop also has a different result than a where clause in a for loop. > The where_clause appears in the for in statement > > for_in_statement : 'for' 'case'? pattern 'in' expression where_clause? > code_block > > It's syntactic sugar because the expression can be already be limited through > functional chaining of some sort or another. At the same time, it's nice and > pleasant to have `where` and I'm not itching to throw it out. The same > courtesy could be easily extend to `when` (because I don't really want to use > the `while` keyword here, but I could easily be convinced otherwise because I > don't have a strong stance either way): > > for_in_statement : 'for' 'case'? pattern 'in' expression (where_clause | > when_clause)? code_block > when_clause : 'when' expression > > and again it could be nice and pleasant to have, although not necessary. The > question comes down to how much does the language benefit by this sugar. > > I'd say that in both cases, combining chaining and statements is > marginallyless goodthan either using standalone chaining or statements > without chaining. But as I say this, I know as a fact, I fully intend to use > `sequence(_:, next:).take(while:)` with for0in statements, so I'm starting > from a hypocritical vantage point. > > To summarize, I'm more +0.01 than I am -0.01 on this. > > -- E > p.s. Sorry, wux > > > > > _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution
