blob: a4f74fb9394ae3a7949738e954b64bf9a961c256 [file] [log] [blame]
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range, std.stdio;
import std.typecons : tuple;
ulong counter = 0;
double fun(int x)
{
++counter;
// http://en.wikipedia.org/wiki/Quartic_function
return ( (x + 4.0) * (x + 1.0) * (x - 1.0) * (x - 3.0) ) / 14.0 + 0.5;
}
// Without cache, with array (greedy)
auto result1 = iota(-4, 5).map!(a =>tuple(a, fun(a)))()
.filter!(a => a[1] < 0)()
.map!(a => a[0])()
.array();
// the values of x that have a negative y are:
assert(equal(result1, [-3, -2, 2]));
// Check how many times fun was evaluated.
// As many times as the number of items in both source and result.
assert(counter == iota(-4, 5).length + result1.length);
counter = 0;
// Without array, with cache (lazy)
auto result2 = iota(-4, 5).map!(a =>tuple(a, fun(a)))()
.cache()
.filter!(a => a[1] < 0)()
.map!(a => a[0])();
// the values of x that have a negative y are:
assert(equal(result2, [-3, -2, 2]));
// Check how many times fun was evaluated.
// Only as many times as the number of items in source.
assert(counter == iota(-4, 5).length);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range;
int i = 0;
auto r = iota(0, 4).tee!((a){i = a;}, No.pipeOnPop);
auto r1 = r.take(3).cache();
auto r2 = r.cache().take(3);
assert(equal(r1, [0, 1, 2]));
assert(i == 2); //The last "seen" element was 2. The data in cache has been cleared.
assert(equal(r2, [0, 1, 2]));
assert(i == 3); //cache has accessed 3. It is still stored internally by cache.
}
@safe @nogc unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : chain, only;
auto squares =
chain(only(1, 2, 3, 4), only(5, 6)).map!(a => a * a);
assert(equal(squares, only(1, 4, 9, 16, 25, 36)));
}
@safe unittest
{
import std.algorithm.iteration;
auto sums = [2, 4, 6, 8];
auto products = [1, 4, 9, 16];
size_t i = 0;
foreach (result; [ 1, 2, 3, 4 ].map!("a + a", "a * a"))
{
assert(result[0] == sums[i]);
assert(result[1] == products[i]);
++i;
}
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.conv : to;
alias stringize = map!(to!string);
assert(equal(stringize([ 1, 2, 3, 4 ]), [ "1", "2", "3", "4" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.range : iota;
import std.typecons : No;
int[] arr;
iota(5).each!(n => arr ~= n);
assert(arr == [0, 1, 2, 3, 4]);
// stop iterating early
iota(5).each!((n) { arr ~= n; return No.each; });
assert(arr == [0, 1, 2, 3, 4, 0]);
// If the range supports it, the value can be mutated in place
arr.each!((ref n) => n++);
assert(arr == [1, 2, 3, 4, 5, 1]);
arr.each!"a++";
assert(arr == [2, 3, 4, 5, 6, 2]);
auto m = arr.map!(n => n);
// by-ref lambdas are not allowed for non-ref ranges
static assert(!__traits(compiles, m.each!((ref n) => n++)));
// The default predicate consumes the range
(&m).each();
assert(m.empty);
}
@safe unittest
{
import std.algorithm.iteration;
auto arr = new size_t[4];
arr.each!"a=i"();
assert(arr == [0, 1, 2, 3]);
arr.each!((i, ref e) => e = i * 2);
assert(arr == [0, 2, 4, 6]);
}
@system unittest
{
import std.algorithm.iteration;
static class S
{
int x;
int opApply(scope int delegate(ref int _x) dg) { return dg(x); }
}
auto s = new S;
s.each!"a++";
assert(s.x == 1);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.math.operations : isClose;
import std.range;
int[] arr = [ 1, 2, 3, 4, 5 ];
// Filter below 3
auto small = filter!(a => a < 3)(arr);
assert(equal(small, [ 1, 2 ]));
// Filter again, but with Uniform Function Call Syntax (UFCS)
auto sum = arr.filter!(a => a < 3);
assert(equal(sum, [ 1, 2 ]));
// In combination with chain() to span multiple ranges
int[] a = [ 3, -2, 400 ];
int[] b = [ 100, -101, 102 ];
auto r = chain(a, b).filter!(a => a > 0);
assert(equal(r, [ 3, 400, 100, 102 ]));
// Mixing convertible types is fair game, too
double[] c = [ 2.5, 3.0 ];
auto r1 = chain(c, a, b).filter!(a => cast(int) a != a);
assert(isClose(r1, [ 2.5 ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range;
int[] arr = [ 1, 2, 3, 4, 5 ];
auto small = filterBidirectional!("a < 3")(arr);
static assert(isBidirectionalRange!(typeof(small)));
assert(small.back == 2);
assert(equal(small, [ 1, 2 ]));
assert(equal(retro(small), [ 2, 1 ]));
// In combination with chain() to span multiple ranges
int[] a = [ 3, -2, 400 ];
int[] b = [ 100, -101, 102 ];
auto r = filterBidirectional!("a > 0")(chain(a, b));
assert(r.back == 102);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : tuple, Tuple;
int[] arr = [ 1, 2, 2, 2, 2, 3, 4, 4, 4, 5 ];
assert(equal(group(arr), [ tuple(1, 1u), tuple(2, 4u), tuple(3, 1u),
tuple(4, 3u), tuple(5, 1u) ][]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.sorting : sort;
import std.array : assocArray;
uint[string] result;
auto range = ["a", "b", "a", "c", "b", "c", "c", "d", "e"];
result = range.sort!((a, b) => a < b)
.group
.assocArray;
assert(result == ["a": 2U, "b": 2U, "c": 3U, "d": 1U, "e": 1U]);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
// Grouping by particular attribute of each element:
auto data = [
[1, 1],
[1, 2],
[2, 2],
[2, 3]
];
auto r1 = data.chunkBy!((a,b) => a[0] == b[0]);
assert(r1.equal!equal([
[[1, 1], [1, 2]],
[[2, 2], [2, 3]]
]));
auto r2 = data.chunkBy!((a,b) => a[1] == b[1]);
assert(r2.equal!equal([
[[1, 1]],
[[1, 2], [2, 2]],
[[2, 3]]
]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range.primitives;
import std.typecons : tuple;
// Grouping by particular attribute of each element:
auto range =
[
[1, 1],
[1, 1],
[1, 2],
[2, 2],
[2, 3],
[2, 3],
[3, 3]
];
auto byX = chunkBy!(a => a[0])(range);
auto expected1 =
[
tuple(1, [[1, 1], [1, 1], [1, 2]]),
tuple(2, [[2, 2], [2, 3], [2, 3]]),
tuple(3, [[3, 3]])
];
foreach (e; byX)
{
assert(!expected1.empty);
assert(e[0] == expected1.front[0]);
assert(e[1].equal(expected1.front[1]));
expected1.popFront();
}
auto byY = chunkBy!(a => a[1])(range);
auto expected2 =
[
tuple(1, [[1, 1], [1, 1]]),
tuple(2, [[1, 2], [2, 2]]),
tuple(3, [[2, 3], [2, 3], [3, 3]])
];
foreach (e; byY)
{
assert(!expected2.empty);
assert(e[0] == expected2.front[0]);
assert(e[1].equal(expected2.front[1]));
expected2.popFront();
}
}
nothrow pure @safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : dropExactly;
auto source = [4, 3, 2, 11, 0, -3, -3, 5, 3, 0];
auto result1 = source.splitWhen!((a,b) => a <= b);
assert(result1.save.equal!equal([
[4, 3, 2],
[11, 0, -3],
[-3],
[5, 3, 0]
]));
//splitWhen, like chunkBy, is currently a reference range (this may change
//in future). Remember to call `save` when appropriate.
auto result2 = result1.dropExactly(2);
assert(result1.save.equal!equal([
[-3],
[5, 3, 0]
]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.conv : text;
assert(["abc", "def"].joiner.equal("abcdef"));
assert(["Mary", "has", "a", "little", "lamb"]
.joiner("...")
.equal("Mary...has...a...little...lamb"));
assert(["", "abc"].joiner("xyz").equal("xyzabc"));
assert([""].joiner("xyz").equal(""));
assert(["", ""].joiner("xyz").equal("xyz"));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : repeat;
assert([""].joiner.equal(""));
assert(["", ""].joiner.equal(""));
assert(["", "abc"].joiner.equal("abc"));
assert(["abc", ""].joiner.equal("abc"));
assert(["abc", "def"].joiner.equal("abcdef"));
assert(["Mary", "has", "a", "little", "lamb"].joiner.equal("Maryhasalittlelamb"));
assert("abc".repeat(3).joiner.equal("abcabcabc"));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
auto a = [ [1, 2, 3], [42, 43] ];
auto j = joiner(a);
j.front = 44;
assert(a == [ [44, 2, 3], [42, 43] ]);
assert(equal(j, [44, 2, 3, 42, 43]));
}
@safe pure unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : chain, cycle, iota, only, retro, take, zip;
import std.format : format;
static immutable number = "12345678";
static immutable delimiter = ",";
auto formatted = number.retro
.zip(3.iota.cycle.take(number.length))
.map!(z => chain(z[0].only, z[1] == 2 ? delimiter : null))
.joiner
.retro;
static immutable expected = "12,345,678";
assert(formatted.equal(expected));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : retro;
auto a = [[1, 2, 3], [4, 5]];
auto j = a.joiner;
j.back = 44;
assert(a == [[1, 2, 3], [4, 44]]);
assert(equal(j.retro, [44, 4, 3, 2, 1]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : max, min;
import std.math.operations : isClose;
import std.range;
int[] arr = [ 1, 2, 3, 4, 5 ];
// Sum all elements
auto sum = reduce!((a,b) => a + b)(0, arr);
assert(sum == 15);
// Sum again, using a string predicate with "a" and "b"
sum = reduce!"a + b"(0, arr);
assert(sum == 15);
// Compute the maximum of all elements
auto largest = reduce!(max)(arr);
assert(largest == 5);
// Max again, but with Uniform Function Call Syntax (UFCS)
largest = arr.reduce!(max);
assert(largest == 5);
// Compute the number of odd elements
auto odds = reduce!((a,b) => a + (b & 1))(0, arr);
assert(odds == 3);
// Compute the sum of squares
auto ssquares = reduce!((a,b) => a + b * b)(0, arr);
assert(ssquares == 55);
// Chain multiple ranges into seed
int[] a = [ 3, 4 ];
int[] b = [ 100 ];
auto r = reduce!("a + b")(chain(a, b));
assert(r == 107);
// Mixing convertible types is fair game, too
double[] c = [ 2.5, 3.0 ];
auto r1 = reduce!("a + b")(chain(a, b, c));
assert(isClose(r1, 112.5));
// To minimize nesting of parentheses, Uniform Function Call Syntax can be used
auto r2 = chain(a, b, c).reduce!("a + b");
assert(isClose(r2, 112.5));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : max, min;
import std.math.operations : isClose;
import std.math.algebraic : sqrt;
import std.typecons : tuple, Tuple;
double[] a = [ 3.0, 4, 7, 11, 3, 2, 5 ];
// Compute minimum and maximum in one pass
auto r = reduce!(min, max)(a);
// The type of r is Tuple!(int, int)
assert(isClose(r[0], 2)); // minimum
assert(isClose(r[1], 11)); // maximum
// Compute sum and sum of squares in one pass
r = reduce!("a + b", "a + b * b")(tuple(0.0, 0.0), a);
assert(isClose(r[0], 35)); // sum
assert(isClose(r[1], 233)); // sum of squares
// Compute average and standard deviation from the above
auto avg = r[0] / a.length;
assert(avg == 5);
auto stdev = sqrt(r[1] / a.length - avg * avg);
assert(cast(int) stdev == 2);
}
@safe pure unittest
{
import std.algorithm.iteration;
immutable arr = [1, 2, 3, 4, 5];
// Sum all elements
assert(arr.fold!((a, e) => a + e) == 15);
// Sum all elements with explicit seed
assert(arr.fold!((a, e) => a + e)(6) == 21);
import std.algorithm.comparison : min, max;
import std.typecons : tuple;
// Compute minimum and maximum at the same time
assert(arr.fold!(min, max) == tuple(1, 5));
// Compute minimum and maximum at the same time with seeds
assert(arr.fold!(min, max)(0, 7) == tuple(0, 7));
// Can be used in a UFCS chain
assert(arr.map!(a => a + 1).fold!((a, e) => a + e) == 20);
// Return the last element of any range
assert(arr.fold!((a, e) => e) == 5);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : max, min;
import std.array : array;
import std.math.operations : isClose;
import std.range : chain;
int[] arr = [1, 2, 3, 4, 5];
// Partial sum of all elements
auto sum = cumulativeFold!((a, b) => a + b)(arr, 0);
assert(sum.array == [1, 3, 6, 10, 15]);
// Partial sum again, using a string predicate with "a" and "b"
auto sum2 = cumulativeFold!"a + b"(arr, 0);
assert(sum2.array == [1, 3, 6, 10, 15]);
// Compute the partial maximum of all elements
auto largest = cumulativeFold!max(arr);
assert(largest.array == [1, 2, 3, 4, 5]);
// Partial max again, but with Uniform Function Call Syntax (UFCS)
largest = arr.cumulativeFold!max;
assert(largest.array == [1, 2, 3, 4, 5]);
// Partial count of odd elements
auto odds = arr.cumulativeFold!((a, b) => a + (b & 1))(0);
assert(odds.array == [1, 1, 2, 2, 3]);
// Compute the partial sum of squares
auto ssquares = arr.cumulativeFold!((a, b) => a + b * b)(0);
assert(ssquares.array == [1, 5, 14, 30, 55]);
// Chain multiple ranges into seed
int[] a = [3, 4];
int[] b = [100];
auto r = cumulativeFold!"a + b"(chain(a, b));
assert(r.array == [3, 7, 107]);
// Mixing convertible types is fair game, too
double[] c = [2.5, 3.0];
auto r1 = cumulativeFold!"a + b"(chain(a, b, c));
assert(isClose(r1, [3, 7, 107, 109.5, 112.5]));
// To minimize nesting of parentheses, Uniform Function Call Syntax can be used
auto r2 = chain(a, b, c).cumulativeFold!"a + b";
assert(isClose(r2, [3, 7, 107, 109.5, 112.5]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : max, min;
import std.algorithm.iteration : map;
import std.math.operations : isClose;
import std.typecons : tuple;
double[] a = [3.0, 4, 7, 11, 3, 2, 5];
// Compute minimum and maximum in one pass
auto r = a.cumulativeFold!(min, max);
// The type of r is Tuple!(int, int)
assert(isClose(r.map!"a[0]", [3, 3, 3, 3, 3, 2, 2])); // minimum
assert(isClose(r.map!"a[1]", [3, 4, 7, 11, 11, 11, 11])); // maximum
// Compute sum and sum of squares in one pass
auto r2 = a.cumulativeFold!("a + b", "a + b * b")(tuple(0.0, 0.0));
assert(isClose(r2.map!"a[0]", [3, 7, 14, 25, 28, 30, 35])); // sum
assert(isClose(r2.map!"a[1]", [9, 25, 74, 195, 204, 208, 233])); // sum of squares
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
assert("a|bc|def".splitter('|').equal([ "a", "bc", "def" ]));
int[] a = [1, 0, 2, 3, 0, 4, 5, 6];
int[][] w = [ [1], [2, 3], [4, 5, 6] ];
assert(a.splitter(0).equal(w));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
assert("a|bc|def".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "a", "|", "bc", "|", "def" ]));
int[] a = [1, 0, 2, 3, 0, 4, 5, 6];
int[][] w = [ [1], [0], [2, 3], [0], [4, 5, 6] ];
assert(a.splitter!("a == b", Yes.keepSeparators)(0).equal(w));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
assert("|ab|".splitter('|').equal([ "", "ab", "" ]));
assert("ab".splitter('|').equal([ "ab" ]));
assert("a|b||c".splitter('|').equal([ "a", "b", "", "c" ]));
assert("hello world".splitter(' ').equal([ "hello", "", "world" ]));
auto a = [ 1, 2, 0, 0, 3, 0, 4, 5, 0 ];
auto w = [ [1, 2], [], [3], [4, 5], [] ];
assert(a.splitter(0).equal(w));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
assert("|ab|".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "", "|", "ab", "|", "" ]));
assert("ab".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "ab" ]));
assert("a|b||c".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "a", "|", "b", "|", "", "|", "c" ]));
assert("hello world".splitter!("a == b", Yes.keepSeparators)(' ')
.equal([ "hello", " ", "", " ", "world" ]));
auto a = [ 1, 2, 0, 0, 3, 0, 4, 5, 0 ];
auto w = [ [1, 2], [0], [], [0], [3], [0], [4, 5], [0], [] ];
assert(a.splitter!("a == b", Yes.keepSeparators)(0).equal(w));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : empty;
assert("".splitter('|').empty);
assert("|".splitter('|').equal([ "", "" ]));
assert("||".splitter('|').equal([ "", "", "" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
import std.range : empty;
assert("".splitter!("a == b", Yes.keepSeparators)('|').empty);
assert("|".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "", "|", "" ]));
assert("||".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "", "|", "", "|", "" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
assert("a=>bc=>def".splitter("=>").equal([ "a", "bc", "def" ]));
assert("a|b||c".splitter("||").equal([ "a|b", "c" ]));
assert("hello world".splitter(" ").equal([ "hello", "world" ]));
int[] a = [ 1, 2, 0, 0, 3, 0, 4, 5, 0 ];
int[][] w = [ [1, 2], [3, 0, 4, 5, 0] ];
assert(a.splitter([0, 0]).equal(w));
a = [ 0, 0 ];
assert(a.splitter([0, 0]).equal([ (int[]).init, (int[]).init ]));
a = [ 0, 0, 1 ];
assert(a.splitter([0, 0]).equal([ [], [1] ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
assert("a=>bc=>def".splitter!("a == b", Yes.keepSeparators)("=>")
.equal([ "a", "=>", "bc", "=>", "def" ]));
assert("a|b||c".splitter!("a == b", Yes.keepSeparators)("||")
.equal([ "a|b", "||", "c" ]));
assert("hello world".splitter!("a == b", Yes.keepSeparators)(" ")
.equal([ "hello", " ", "world" ]));
int[] a = [ 1, 2, 0, 0, 3, 0, 4, 5, 0 ];
int[][] w = [ [1, 2], [0, 0], [3, 0, 4, 5, 0] ];
assert(a.splitter!("a == b", Yes.keepSeparators)([0, 0]).equal(w));
a = [ 0, 0 ];
assert(a.splitter!("a == b", Yes.keepSeparators)([0, 0])
.equal([ (int[]).init, [0, 0], (int[]).init ]));
a = [ 0, 0, 1 ];
assert(a.splitter!("a == b", Yes.keepSeparators)([0, 0])
.equal([ [], [0, 0], [1] ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.ascii : toLower;
assert("abXcdxef".splitter!"a.toLower == b"('x').equal(
[ "ab", "cd", "ef" ]));
auto w = [ [0], [1], [2] ];
assert(w.splitter!"a.front == b"(1).equal([ [[0]], [[2]] ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
import std.ascii : toLower;
assert("abXcdxef".splitter!("a.toLower == b", Yes.keepSeparators)('x')
.equal([ "ab", "X", "cd", "x", "ef" ]));
auto w = [ [0], [1], [2] ];
assert(w.splitter!("a.front == b", Yes.keepSeparators)(1)
.equal([ [[0]], [[1]], [[2]] ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range.primitives : front;
assert(equal(splitter!(a => a == '|')("a|bc|def"), [ "a", "bc", "def" ]));
assert(equal(splitter!(a => a == ' ')("hello world"), [ "hello", "", "world" ]));
int[] a = [ 1, 2, 0, 0, 3, 0, 4, 5, 0 ];
int[][] w = [ [1, 2], [], [3], [4, 5], [] ];
assert(equal(splitter!(a => a == 0)(a), w));
a = [ 0 ];
assert(equal(splitter!(a => a == 0)(a), [ (int[]).init, (int[]).init ]));
a = [ 0, 1 ];
assert(equal(splitter!(a => a == 0)(a), [ [], [1] ]));
w = [ [0], [1], [2] ];
assert(equal(splitter!(a => a.front == 1)(w), [ [[0]], [[2]] ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
assert("|ab|".splitter('|').equal([ "", "ab", "" ]));
assert("ab".splitter('|').equal([ "ab" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
assert("|ab|".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "", "|", "ab", "|", "" ]));
assert("ab".splitter!("a == b", Yes.keepSeparators)('|')
.equal([ "ab" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : retro;
assert("a|bc|def".splitter('|').retro.equal([ "def", "bc", "a" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.typecons : Yes;
import std.range : retro;
assert("a|bc|def".splitter!("a == b", Yes.keepSeparators)('|')
.retro.equal([ "def", "|", "bc", "|", "a" ]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.ascii : isWhite;
import std.algorithm.comparison : equal;
import std.algorithm.iteration : splitter;
string str = "Hello World!";
assert(str.splitter!(isWhite).equal(["Hello", "World!"]));
}
@safe pure unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
auto a = " a bcd ef gh ";
assert(equal(splitter(a), ["a", "bcd", "ef", "gh"][]));
}
@safe pure unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
// substitute single elements
assert("do_it".substitute('_', ' ').equal("do it"));
// substitute multiple, single elements
assert("do_it".substitute('_', ' ',
'd', 'g',
'i', 't',
't', 'o')
.equal("go to"));
// substitute subranges
assert("do_it".substitute("_", " ",
"do", "done")
.equal("done it"));
// substitution works for any ElementType
int[] x = [1, 2, 3];
auto y = x.substitute(1, 0.1);
assert(y.equal([0.1, 2, 3]));
static assert(is(typeof(y.front) == double));
import std.range : retro;
assert([1, 2, 3].substitute(1, 0.1).retro.equal([3, 2, 0.1]));
}
@safe pure unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
// substitute subranges of a range
assert("apple_tree".substitute!("apple", "banana",
"tree", "shrub").equal("banana_shrub"));
// substitute subranges of a range
assert("apple_tree".substitute!('a', 'b',
't', 'f').equal("bpple_free"));
// substitute values
assert('a'.substitute!('a', 'b', 't', 'f') == 'b');
}
@safe pure unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range.primitives : ElementType;
int[3] x = [1, 2, 3];
auto y = x[].substitute(1, 0.1)
.substitute(0.1, 0.2);
static assert(is(typeof(y.front) == double));
assert(y.equal([0.2, 2, 3]));
auto z = "42".substitute('2', '3')
.substitute('3', '1');
static assert(is(ElementType!(typeof(z)) == dchar));
assert(equal(z, "41"));
}
@safe pure nothrow unittest
{
import std.algorithm.iteration;
import std.range;
//simple integral sumation
assert(sum([ 1, 2, 3, 4]) == 10);
//with integral promotion
assert(sum([false, true, true, false, true]) == 3);
assert(sum(ubyte.max.repeat(100)) == 25500);
//The result may overflow
assert(uint.max.repeat(3).sum() == 4294967293U );
//But a seed can be used to change the sumation primitive
assert(uint.max.repeat(3).sum(ulong.init) == 12884901885UL);
//Floating point sumation
assert(sum([1.0, 2.0, 3.0, 4.0]) == 10);
//Floating point operations have double precision minimum
static assert(is(typeof(sum([1F, 2F, 3F, 4F])) == double));
assert(sum([1F, 2, 3, 4]) == 10);
//Force pair-wise floating point sumation on large integers
import std.math.operations : isClose;
assert(iota(ulong.max / 2, ulong.max / 2 + 4096).sum(0.0)
.isClose((ulong.max / 2) * 4096.0 + 4096^^2 / 2));
}
@safe @nogc pure nothrow unittest
{
import std.algorithm.iteration;
import std.math.operations : isClose;
import std.math.traits : isNaN;
static immutable arr1 = [1, 2, 3];
static immutable arr2 = [1.5, 2.5, 12.5];
assert(arr1.mean.isClose(2));
assert(arr2.mean.isClose(5.5));
assert(arr1[0 .. 0].mean.isNaN);
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.algorithm.mutation : copy;
int[] arr = [ 1, 2, 2, 2, 2, 3, 4, 4, 4, 5 ];
assert(equal(uniq(arr), [ 1, 2, 3, 4, 5 ][]));
// Filter duplicates in-place using copy
arr.length -= arr.uniq().copy(arr).length;
assert(arr == [ 1, 2, 3, 4, 5 ]);
// Note that uniqueness is only determined consecutively; duplicated
// elements separated by an intervening different element will not be
// eliminated:
assert(equal(uniq([ 1, 1, 2, 1, 1, 3, 1]), [1, 2, 1, 3, 1]));
}
@safe unittest
{
import std.algorithm.iteration;
import std.algorithm.comparison : equal;
import std.range : iota;
assert(equal!equal(iota(3).permutations,
[[0, 1, 2],
[1, 0, 2],
[2, 0, 1],
[0, 2, 1],
[1, 2, 0],
[2, 1, 0]]));
}