import std.stdio, std.algorithm, std.range;

void main()
{
    writeln( find([5, 1, 2, 3, 4, 5, 1], 5) );
    writeln( find(retro([5, 1, 2, 3, 4, 5, 1]), 5) );
}

Output:
[5, 1, 2, 3, 4, 5, 1]
[5, 4, 3, 2, 1, 5]

The docs for find are:
"returns : haystack advanced such that binaryFun!pred(haystack.front, needle) 
is true "
"To find the last occurence of needle in haystack, call find(retro(haystack), 
needle). "

To me, if I was looking for the last element in a range I would expect to get a 
range with the found element followed by an elements after it. Obviously retro 
reverses the range (it just hard-wires front=back, back=front for those not in 
the know), so this code is correct.

Still, I would expect that finding a last element in this range:
[5, 1, 2, 3, 4, 5, 1]

would return the range:
[5, 1]

and not:
[5, 4, 3, 2, 1, 5]

Isn't that what most people would want when they're looking for the last 
matching element?

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