• d-bugmail puremagic.com (34/34) Sep 03 2021 https://issues.dlang.org/show_bug.cgi?id=22272

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=22272

          Issue ID: 22272
           Summary: [std.range.retro] should behave the same as
                    foreach_reverse
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody puremagic.com
          Reporter: jlourenco5691 gmail.com

The Range retro follows the current Range hierarchy. This brings friction when
working with this range because it forces the user to implement a 'save'
method. Iterating a retro range should be the same as iterating with a
foreach_reverse. The foreach_reverse allows iterating ranges without the 'save'
method implementation. I would even argue that 'popFront' and 'front' shouldn't
be required because once again foreach_reverse allows that.

---
struct Foo
{
    void popBack() { i--; }
    bool empty() { return !i; }
    auto back() { return i; }

    int i = 1;
}

void main()
{
    foreach_reverse(_; Foo.init) {}
}
---

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