On Wednesday, 10 August 2016 at 18:08:02 UTC, Lodovico Giaretta
wrote:
I'm probably missing something stupid but...
Why on earth do the two loops in main print a different result?
It looks like the foreach lowering is ignoring my definition of
front...
=====================================================
import std.stdio, std.container.array;
struct RangeWrapper(Range)
{
Range range;
alias range this;
auto front()
{
return range.front + 1;
}
}
auto rangeWrapper(Range)(auto ref Range range)
{
return RangeWrapper!Range(range);
}
void main()
{
Array!int array;
array.insertBack(3);
foreach (i; rangeWrapper(array[]))
writeln(i); // prints 3, which is wrong
// isn't the above foreach equivalent to the following
loop ?
for (auto r = rangeWrapper(array[]); !r.empty; r.popFront())
writeln(r.front); // correctly prints 4
}
=====================================================
Thank you for your help.
This actually only happens with std.container.Array. Other ranges
are ok. Even stranger...
