https://issues.dlang.org/show_bug.cgi?id=24152

          Issue ID: 24152
           Summary: range .until evaluates .front twice
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: minor
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: d.bugs@webfreak.org

```
import std.algorithm : map, until;
import std.range : iota;
import std.array : array;

int access;
int logAccess(int x) {
    access++;
    return x;
}

void main()
{
    iota(10).map!logAccess.until(10).array;

    assert(access == 20);
}
```

if you remove the `.until(10)`, you get `access == 10`

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