[Issue 8334] New: find cannot handle close match at end of haystack in needle isn't bi-directional

[d-bugmail at puremagic.com]

http://d.puremagic.com/issues/show_bug.cgi?id=8334

           Summary: find cannot handle close match at end of haystack in
                    needle isn't bi-directional
           Product: D
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Phobos
        AssignedTo: nobody at puremagic.com
        ReportedBy: jmdavisProg at gmx.com


--- Comment #0 from Jonathan M Davis <jmdavisProg at gmx.com> 2012-07-01 15:08:02 PDT ---
This code

import std.array;
import std.algorithm;

void main()
{
    auto haystack = [1, 2, 3, 4, 1, 9, 12, 42];
    auto needle = filter!"true"([12, 42, 27]);
    assert(find(haystack, needle).empty);
}

results in this

core.exception.RangeError at std.algorithm(3255): Range violation
----------------
./q(_d_array_bounds+0x26) [0x436112]
./q() [0x42d9c9]
./q(int[] std.algorithm.find!("a == b", int[],
std.algorithm.filter!("true").filter!(int[]).filter.FilteredRange).find(int[],
std.algorithm.filter!("true").filter!(int[]).filter,
std.algorithm.filter!("true").filter!(int[]).filter.FilteredRange.FilteredRange
function(int[]))+0xc8) [0x42b748]
./q(_Dmain+0xc9) [0x42b149]
./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x42c818]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
delegate())+0x2a) [0x42c192]
./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x42c85f]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
delegate())+0x2a) [0x42c192]
./q(main+0xd1) [0x42c11d]
/lib/libc.so.6(__libc_start_main+0xf5) [0x7f25ecccc455]
----------------

If needle is an array rather than a filtered range, it's fine, and if the
mismatch is before the end of the haystack, it's fine, but that particular
overload of find cannot handle having the beginning of the needle match the end
of the haystack when the needle is longer than the remainder of the haystack:

R1 find(alias pred = "a == b", R1, R2)(R1 haystack, R2 needle)
if (isRandomAccessRange!R1 && isForwardRange!R2 && !isBidirectionalRange!R2
        && is(typeof(binaryFun!pred(haystack.front, needle.front)) : bool))

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