Bug 16642 – byCodeUnit doesn't work AutodecodableStrings unless they're actually strings or alias a variable that's a string

This code fails to compile import std.utf; struct S { string s; string str() { return s; } alias str this; } void main() { auto s = S("hello"); auto range = byCodeUnit(s); } Similarly, this fails to compile import std.utf; enum E { a = "hello" } void main() { auto s = E.a; auto range = byCodeUnit(s); } Also, this compiles but uses the alias rather than the range API and thus fails the assertion: import std.range.primitives; import std.utf; static struct RangeAndStringish { string data; string s; alias s this; bool empty() { return data.empty; } char front() { return data[0]; } void popFront() { data = data[1 .. $]; } } void main() { auto fn = RangeAndStringish("test.d", "other"); auto x = fn.byCodeUnit(); assert(x.front == 't'); } I suppose that it could be argued that this last case is doing the right thing - or at least that it's ambiguous, but normally, an implicit conversion is only supposed to be used if the type itself doesn't work directly, and in this case, the type itself would work without the implicit conversion.

Commits pushed to master at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/6e3d41cfe92d0af0360002db6436d2ec98f503af Fix issue 16642: byCodeUnit doesn't work properly with alias this. If a template is going to allow implicit conversions, it really needs to force the conversion in order to avoid subtle bugs. This fixes byCodeUnit so that it forces the conversion to a string type for types that convert implicitly. It also fixes it so that types which implicitly convert to a string type but are also ranges of characters without the conversion will not be converted by byCodeUnit. https://github.com/dlang/phobos/commit/13b3da64a81360e96bab3d1bb09a3a42b751da36 Merge pull request #4879 from jmdavis/issue_16642 Fix Issue 16642 - byCodeUnit doesn't work properly with alias this.

Commits pushed to stable at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/6e3d41cfe92d0af0360002db6436d2ec98f503af Fix issue 16642: byCodeUnit doesn't work properly with alias this. https://github.com/dlang/phobos/commit/13b3da64a81360e96bab3d1bb09a3a42b751da36 Merge pull request #4879 from jmdavis/issue_16642

Commits pushed to newCTFE at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/6e3d41cfe92d0af0360002db6436d2ec98f503af Fix issue 16642: byCodeUnit doesn't work properly with alias this. https://github.com/dlang/phobos/commit/13b3da64a81360e96bab3d1bb09a3a42b751da36 Merge pull request #4879 from jmdavis/issue_16642

Commits pushed to dmd-cxx at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/6e3d41cfe92d0af0360002db6436d2ec98f503af Fix issue 16642: byCodeUnit doesn't work properly with alias this. https://github.com/dlang/phobos/commit/13b3da64a81360e96bab3d1bb09a3a42b751da36 Merge pull request #4879 from jmdavis/issue_16642