Transversal

Given a range of ranges, iterate transversally through the nth element of each of the enclosed ranges. This function is similar to unzip in other languages.

struct Transversal(Ror, TransverseOptions opt = TransverseOptions.assumeJagged)
struct Transversal (
Ror
TransverseOptions opt = TransverseOptions.assumeJagged
) {
this(RangeOfRanges input, size_t n);
enum bool empty;
auto ref front [@property getter];
E moveFront();
E front [@property setter];
void popFront();
typeof(this) save [@property getter];
auto ref back [@property getter];
void popBack();
E moveBack();
E back [@property setter];
auto ref opIndex(size_t n);
E moveAt(size_t n);
void opIndexAssign(E val, size_t n);
size_t length [@property getter];
typeof(this) opSlice(size_t lower, size_t upper);
}
Transversal!(RangeOfRanges, opt) transversal(RangeOfRanges rr, size_t n)

Constructors

this this(RangeOfRanges input, size_t n): Construction from an input and an index.

Members

Functions

moveAt E moveAt(size_t n): Random-access primitive. It is offered if isRandomAccessRange!RangeOfRanges && (opt == TransverseOptions.assumeNotJagged || opt == TransverseOptions.enforceNotJagged).
moveBack E moveBack(): Bidirectional primitives. They are offered if isBidirectionalRange!RangeOfRanges.
moveFront E moveFront(): Forward range primitives.
opIndex auto ref opIndex(size_t n)
opIndexAssign void opIndexAssign(E val, size_t n): Random-access primitive. It is offered if isRandomAccessRange!RangeOfRanges && (opt == TransverseOptions.assumeNotJagged || opt == TransverseOptions.enforceNotJagged).
opSlice typeof(this) opSlice(size_t lower, size_t upper): Slicing if offered if RangeOfRanges supports slicing and all the conditions for supporting indexing are met.
popBack void popBack(): Bidirectional primitives. They are offered if isBidirectionalRange!RangeOfRanges.
popFront void popFront(): Forward range primitives.

Properties

back auto ref back [@property getter]
E back [@property setter]: Bidirectional primitives. They are offered if isBidirectionalRange!RangeOfRanges.
front auto ref front [@property getter]
E front [@property setter]: Forward range primitives.
length size_t length [@property getter]: Random-access primitive. It is offered if isRandomAccessRange!RangeOfRanges && (opt == TransverseOptions.assumeNotJagged || opt == TransverseOptions.enforceNotJagged).
save typeof(this) save [@property getter]: Forward range primitives.

Variables

empty enum bool empty;: Forward range primitives.

Return Value

At minimum, an input range. Range primitives such as bidirectionality and random access are given if the element type of rr provides them.

Examples

import std.algorithm.comparison : equal;
int[][] x = new int[][2];
x[0] = [1, 2];
x[1] = [3, 4];
auto ror = transversal(x, 1);
assert(equal(ror, [ 2, 4 ]));

The following code does a full unzip

import std.algorithm.comparison : equal;
import std.algorithm.iteration : map;
int[][] y = [[1, 2, 3], [4, 5, 6]];
auto z = y.front.walkLength.iota.map!(i => transversal(y, i));
assert(equal!equal(z, [[1, 4], [2, 5], [3, 6]]));