On Thursday, 14 August 2014 at 20:48:42 UTC, Nordlöw wrote:
Ooops, I just realized that we can't express current Phobos
implementations using my variant. Current algorithms take
ranges not range values as a needle. My mistake. Are my
overloads still wanted?
Ok. I finally understood that a simplification was the way to go:
/** Simpler Variant of Phobos' findSplitBefore. */
auto findSplitBefore(alias pred, R1)(R1 haystack) if
(isForwardRange!R1)
{
static if (isSomeString!R1 ||
sRandomAccessRange!R1)
{
auto balance = haystack.find!pred;
immutable pos = haystack.length - balance.length;
return tuple(haystack[0 .. pos],
haystack[pos .. haystack.length]);
}
else
{
auto original = haystack.save;
auto h = haystack.save;
size_t pos;
while (!h.empty)
{
if (unaryFun!pred(h.front))
{
h.popFront();
}
else
{
haystack.popFront();
h = haystack.save;
++pos;
}
}
return tuple(takeExactly(original, pos),
haystack);
}
}
unittest
{
import std.algorithm: equal;
import std.ascii: isDigit;
auto x = "11ab".findSplitBefore!(a => !a.isDigit);
assert(equal(x[0], "11"));
assert(equal(x[1], "ab"));
}
Should this go into Phobos?
