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Replace overload constraints with static if #5145

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129 changes: 65 additions & 64 deletions std/algorithm/comparison.d
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Original file line number Diff line number Diff line change
Expand Up @@ -604,84 +604,85 @@ Returns:

*/
int cmp(alias pred = "a < b", R1, R2)(R1 r1, R2 r2)
if (isInputRange!R1 && isInputRange!R2 && !(isSomeString!R1 && isSomeString!R2))
if (isInputRange!R1 && isInputRange!R2 || isSomeString!R1 && isSomeString!R2)
{
for (;; r1.popFront(), r2.popFront())
static if (isInputRange!R1 && isInputRange!R2)
{
if (r1.empty) return -cast(int)!r2.empty;
if (r2.empty) return !r1.empty;
auto a = r1.front, b = r2.front;
if (binaryFun!pred(a, b)) return -1;
if (binaryFun!pred(b, a)) return 1;
for (;; r1.popFront(), r2.popFront())
{
if (r1.empty) return -cast(int)!r2.empty;
if (r2.empty) return !r1.empty;
auto a = r1.front, b = r2.front;
if (binaryFun!pred(a, b)) return -1;
if (binaryFun!pred(b, a)) return 1;
}
}
}

/// ditto
int cmp(alias pred = "a < b", R1, R2)(R1 r1, R2 r2) if (isSomeString!R1 && isSomeString!R2)
{
import core.stdc.string : memcmp;
import std.utf : decode;

static if (is(typeof(pred) : string))
enum isLessThan = pred == "a < b";
else
enum isLessThan = false;

// For speed only
static int threeWay(size_t a, size_t b)
{
static if (size_t.sizeof == int.sizeof && isLessThan)
return a - b;
else
return binaryFun!pred(b, a) ? 1 : binaryFun!pred(a, b) ? -1 : 0;
}
// For speed only
// @@@BUG@@@ overloading should be allowed for nested functions
static int threeWayInt(int a, int b)
{
static if (isLessThan)
return a - b;
import core.stdc.string : memcmp;
import std.utf : decode;

static if (is(typeof(pred) : string))
enum isLessThan = pred == "a < b";
else
return binaryFun!pred(b, a) ? 1 : binaryFun!pred(a, b) ? -1 : 0;
}
enum isLessThan = false;

static if (typeof(r1[0]).sizeof == typeof(r2[0]).sizeof && isLessThan)
{
static if (typeof(r1[0]).sizeof == 1)
// For speed only
static int threeWay(size_t a, size_t b)
{
immutable len = min(r1.length, r2.length);
immutable result = __ctfe ?
{
foreach (i; 0 .. len)
{
if (r1[i] != r2[i])
return threeWayInt(r1[i], r2[i]);
}
return 0;
}()
: () @trusted { return memcmp(r1.ptr, r2.ptr, len); }();
if (result) return result;
static if (size_t.sizeof == int.sizeof && isLessThan)
return a - b;
else
return binaryFun!pred(b, a) ? 1 : binaryFun!pred(a, b) ? -1 : 0;
}
else
// For speed only
// @@@BUG@@@ overloading should be allowed for nested functions
static int threeWayInt(int a, int b)
{
auto p1 = r1.ptr, p2 = r2.ptr,
pEnd = p1 + min(r1.length, r2.length);
for (; p1 != pEnd; ++p1, ++p2)
static if (isLessThan)
return a - b;
else
return binaryFun!pred(b, a) ? 1 : binaryFun!pred(a, b) ? -1 : 0;
}

static if (typeof(r1[0]).sizeof == typeof(r2[0]).sizeof && isLessThan)
{
static if (typeof(r1[0]).sizeof == 1)
{
immutable len = min(r1.length, r2.length);
immutable result = __ctfe ?
{
foreach (i; 0 .. len)
{
if (r1[i] != r2[i])
return threeWayInt(r1[i], r2[i]);
}
return 0;
}()
: () @trusted { return memcmp(r1.ptr, r2.ptr, len); }();
if (result) return result;
}
else
{
if (*p1 != *p2) return threeWayInt(cast(int) *p1, cast(int) *p2);
auto p1 = r1.ptr, p2 = r2.ptr,
pEnd = p1 + min(r1.length, r2.length);
for (; p1 != pEnd; ++p1, ++p2)
{
if (*p1 != *p2) return threeWayInt(cast(int) *p1, cast(int) *p2);
}
}
return threeWay(r1.length, r2.length);
}
return threeWay(r1.length, r2.length);
}
else
{
for (size_t i1, i2;;)
else
{
if (i1 == r1.length) return threeWay(i2, r2.length);
if (i2 == r2.length) return threeWay(r1.length, i1);
immutable c1 = decode(r1, i1),
c2 = decode(r2, i2);
if (c1 != c2) return threeWayInt(cast(int) c1, cast(int) c2);
for (size_t i1, i2;;)
{
if (i1 == r1.length) return threeWay(i2, r2.length);
if (i2 == r2.length) return threeWay(r1.length, i1);
immutable c1 = decode(r1, i1),
c2 = decode(r2, i2);
if (c1 != c2) return threeWayInt(cast(int) c1, cast(int) c2);
}
}
}
}
Expand Down
92 changes: 46 additions & 46 deletions std/algorithm/iteration.d
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Original file line number Diff line number Diff line change
Expand Up @@ -858,6 +858,7 @@ template each(alias pred = "a")
import std.meta : AliasSeq;
import std.traits : Parameters;

private:
alias BinaryArgs = AliasSeq!(pred, "i", "a");

enum isRangeUnaryIterable(R) =
Expand Down Expand Up @@ -886,67 +887,66 @@ template each(alias pred = "a")
(!isForwardRange!R || isDynamicArray!R) &&
(isForeachUnaryIterable!R || isForeachBinaryIterable!R);

public:
void each(Range)(Range r)
if (isRangeIterable!Range && !isForeachIterable!Range)
if (isRangeIterable!Range ||
isForeachIterable!Range ||
__traits(compiles, Parameters!(Parameters!(r.opApply))) ||
__traits(compiles, typeof(range.front).length))
{
debug(each) pragma(msg, "Using while for ", Range.stringof);
static if (isRangeUnaryIterable!Range)
static if (isRangeIterable!Range)
{
while (!r.empty)
debug(each) pragma(msg, "Using while for ", Range.stringof);
static if (isRangeUnaryIterable!Range)
{
cast(void)unaryFun!pred(r.front);
r.popFront();
while (!r.empty)
{
cast(void)unaryFun!pred(r.front);
r.popFront();
}
}
else // if (isRangeBinaryIterable!Range)
{
size_t i = 0;
while (!r.empty)
{
cast(void)binaryFun!BinaryArgs(i, r.front);
r.popFront();
i++;
}
}
}
else // if (isRangeBinaryIterable!Range)
else if (isForeachIterable!Iterable)
{
size_t i = 0;
while (!r.empty)
debug(each) pragma(msg, "Using foreach for ", Iterable.stringof);
static if (isForeachUnaryIterable!Iterable)
{
foreach (ref e; r)
cast(void)unaryFun!pred(e);
}
else // if (isForeachBinaryIterable!Iterable)
{
cast(void)binaryFun!BinaryArgs(i, r.front);
r.popFront();
i++;
foreach (ref i, ref e; r)
cast(void)binaryFun!BinaryArgs(i, e);
}
}
}

void each(Iterable)(auto ref Iterable r)
if (isForeachIterable!Iterable)
{
debug(each) pragma(msg, "Using foreach for ", Iterable.stringof);
static if (isForeachUnaryIterable!Iterable)
else static if (__traits(compiles, Parameters!(Parameters!(r.opApply))))
{
foreach (ref e; r)
cast(void)unaryFun!pred(e);
// opApply with >2 parameters. count the delegate args.
// only works if it is not templated (otherwise we cannot count the args)
auto dg(Parameters!(Parameters!(r.opApply)) params) {
pred(params);
return 0; // tells opApply to continue iteration
}
r.opApply(&dg);
}
else // if (isForeachBinaryIterable!Iterable)
else static if (__traits(compiles, typeof(range.front).length))
{
foreach (ref i, ref e; r)
cast(void)binaryFun!BinaryArgs(i, e);
// range interface with >2 parameters.
for (auto r = range; !r.empty; r.popFront())
pred(r.front.expand);
}
}

// opApply with >2 parameters. count the delegate args.
// only works if it is not templated (otherwise we cannot count the args)
void each(Iterable)(auto ref Iterable r)
if (!isRangeIterable!Iterable && !isForeachIterable!Iterable &&
__traits(compiles, Parameters!(Parameters!(r.opApply))))
{
auto dg(Parameters!(Parameters!(r.opApply)) params) {
pred(params);
return 0; // tells opApply to continue iteration
}
r.opApply(&dg);
}

// range interface with >2 parameters.
void each(Range)(Range range)
if (!isRangeIterable!Range && !isForeachIterable!Range &&
__traits(compiles, typeof(range.front).length))
{
for (auto r = range; !r.empty; r.popFront())
pred(r.front.expand);
}
}

///
Expand Down
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