On Friday, August 05, 2016 15:50:50 H.Loom via Digitalmars-d-learn wrote: > On Friday, 5 August 2016 at 10:25:42 UTC, Nordlöw wrote: > > Should range members front() and back() assert() or throw() on > > emptyness? > > > > If it should assert() doesn't that lead to unsafer code in > > release mode? > > > > What's the consensus here? > > nothing, but examples exist in pbobos such as front() on narrow > strings.
That's because of invalid Unicode, not because the string was empty. It asserts that the string is non-empty. No code anywhere should ever be calling front or back on an empty range, and it is a programming error if it does, not a recoverable error. We obviously don't have control over what everyone else does with their code, but Phobos does not throw an exception in such cases - it asserts if it does anything - and it is definitely the consensus of the main devs that you're not using the range API correctly if code ever calls front or back on an empty range. It is a bug to do so. There were even some recent updates to the documentation to make some of the basic rules around the range primitives clearer, though since it was in the documenation for std.range, it won't be up until the next release: https://github.com/dlang/phobos/pull/4511 - Jonathan M Davis
