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Fixes issue 9299 - std.algorithm.minPos of const(int)[]

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unknown 2013-01-12 13:45:08 +01:00
parent bfb6d3d2f3
commit 5afbfac8c5
1 changed files with 37 additions and 14 deletions
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51
std/algorithm.d
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@ -6103,21 +6103,22 @@ assert(minCount(a) == tuple(1, 3));
assert(minCount!("a > b")(a) == tuple(4, 2)); assert(minCount!("a > b")(a) == tuple(4, 2));
---- ----
*/ */
Tuple!(ElementType!(Range), size_t) Tuple!(ElementType!Range, size_t)
minCount(alias pred = "a < b", Range)(Range range) minCount(alias pred = "a < b", Range)(Range range)
if (isInputRange!Range && !isInfinite!Range) if (isInputRange!Range && !isInfinite!Range &&
is(typeof(binaryFun!pred(range.front, range.front))))
{ {
enforce(!range.empty, "Can't count elements from an empty range"); enforce(!range.empty, "Can't count elements from an empty range");
size_t occurrences = 1; size_t occurrences = 1;
auto p = range.front; auto v = range.front;
for (range.popFront(); !range.empty; range.popFront()) for (range.popFront(); !range.empty; range.popFront())
{ {
auto p2 = range.front; auto v2 = range.front;
if (binaryFun!(pred)(p, p2)) continue; if (binaryFun!pred(v, v2)) continue;
if (binaryFun!(pred)(p2, p)) if (binaryFun!pred(v2, v))
{ {
// change the min // change the min
move(p2, p); move(v2, v);
occurrences = 1; occurrences = 1;
} }
else else
@ -6125,7 +6126,7 @@ minCount(alias pred = "a < b", Range)(Range range)
++occurrences; ++occurrences;
} }
} }
return tuple(p, occurrences); return typeof(return)(v, occurrences);
} }
unittest unittest
@ -6166,21 +6167,19 @@ assert(minPos!("a > b")(a) == [ 4, 1, 2, 4, 1, 1, 2 ]);
---- ----
*/ */
Range minPos(alias pred = "a < b", Range)(Range range) Range minPos(alias pred = "a < b", Range)(Range range)
if (isForwardRange!Range && !isInfinite!Range) if (isForwardRange!Range && !isInfinite!Range &&
is(typeof(binaryFun!pred(range.front, range.front))))
{ {
if (range.empty) return range; if (range.empty) return range;
auto result = range.save; auto result = range.save;
auto p = result.front;
for (range.popFront(); !range.empty; range.popFront()) for (range.popFront(); !range.empty; range.popFront())
{ {
auto p2 = range.front;
//Note: Unlike minCount, we do not care to find equivalence, so a single pred call is enough //Note: Unlike minCount, we do not care to find equivalence, so a single pred call is enough
if (binaryFun!pred(p2, p)) if (binaryFun!pred(range.front, result.front))
{ {
// change the min // change the min
result = range.save; result = range.save;
move(p2, p);
} }
} }
return result; return result;
@ -6203,6 +6202,30 @@ unittest
//test with reference range. //test with reference range.
assert( equal( minPos(new ReferenceForwardRange!int([1, 2, 1, 0, 2, 0])), [0, 2, 0] ) ); assert( equal( minPos(new ReferenceForwardRange!int([1, 2, 1, 0, 2, 0])), [0, 2, 0] ) );
} }
unittest
{
//Rvalue range
debug(std_algorithm) scope(success)
writeln("unittest @", __FILE__, ":", __LINE__, " done.");
assert(Array!int(2, 3, 4, 1, 2, 4, 1, 1, 2)
[]
.minPos()
.equal([ 1, 2, 4, 1, 1, 2 ]));
}
unittest
{
//BUG 9299
debug(std_algorithm) scope(success)
writeln("unittest @", __FILE__, ":", __LINE__, " done.");
immutable a = [ 2, 3, 4, 1, 2, 4, 1, 1, 2 ];
// Minimum is 1 and first occurs in position 3
assert(minPos(a) == [ 1, 2, 4, 1, 1, 2 ]);
// Maximum is 4 and first occurs in position 5
assert(minPos!("a > b")(a) == [ 4, 1, 2, 4, 1, 1, 2 ]);
immutable(int[])[] b = [ [4], [2, 4], [4], [4] ];
assert(minPos!("a[0] < b[0]")(b) == [ [2, 4], [4], [4] ]);
}
// mismatch // mismatch
/** /**