On Friday, 21 July 2017 at 15:13:09 UTC, Timon Gehr wrote:
"in and out expressions must come at the end of the function
declarator suffix, and before the regular contracts, if any"
The implementation actually allows all possible notations for
contracts to be mixed freely. Whether or not 'do' is required
depends on what notation is used by the last contract.
I decided that for grammar purposes it would be easier to require
the contract expressions before the contract blocks. Contract
blocks are currently conflated grammatically with FunctionBody
[1]. An accurate grammar that describes the current
implementation would be twice as complicated, because
FunctionBody would have to be redefined. I want the feature to be
as simple as possible to understand, so I didn't think it was
worth it.
There has also been mention of the possibility of improving the
implementation of contracts to allow separate compilation, in
which case the signature, plus contracts, could some day appear
without the body. I wanted to define the new expressions to
accommodate this possibility.
[1] https://dlang.org/spec/grammar.html#FunctionBody
