thesebas / itertools
itertools for working with genrators/iterators
1.0.3
2017-11-06 08:08 UTC
Requires (Dev)
- kahlan/kahlan: ^4.0
- satooshi/php-coveralls: ^1.0
This package is auto-updated.
Last update: 2024-10-25 12:13:22 UTC
README
Installation
composer require thesebas/itertools
Usage
Lest assume we have some generator that yields letters.
expect(iterator_to_array(gen(3)))->toBe(['a', 'b', 'c']);
tail
Skip all but n
items from Iterator.
$actual = tail(gen(5), 3, false); expect(iterator_to_array($actual))->toBe(['c', 'd', 'e']);
head
Iterator over n
first items.
$actual = head(gen(10), 3); expect(iterator_to_array($actual))->toBe(['a', 'b', 'c']);
skip
Skip n
items and iterate over rest.
$actual = skip(gen(10), 4); expect(iterator_to_array($actual))->toBe(['e', 'f', 'g', 'h', 'i', 'j']);
tee
Split Iterator to two independent Iterators (with internal buffering).
list($left, $right) = tee(gen(10)); expect(iterator_to_array(head($left, 3)))->toBe(['a', 'b', 'c']); expect(iterator_to_array(head($right, 5)))->toBe(['a', 'b', 'c', 'd', 'e']); expect(iterator_to_array(head($left, 5)))->toBe(['d', 'e', 'f', 'g', 'h']); expect(iterator_to_array(head($right, 2)))->toBe(['f', 'g']); expect(iterator_to_array(head($left, 2)))->toBe(['i', 'j']); expect(iterator_to_array(head($right, 3)))->toBe(['h', 'i', 'j']);
chain
Iterate over first, then second, third...
$actual = chain(gen(5), gen(3)); expect(iterator_to_array($actual))->toBe(['a', 'b', 'c', 'd', 'e', 'a', 'b', 'c']);
filter
Iterate ovel all but yield only filtered items.
$actual = filter(gen(10), function ($item, $key) { return $key % 2 == 1; }); expect(iterator_to_array($actual))->toBe(['b', 'd', 'f', 'h', 'j']);
map
Return new Iterator with mapped values
$actual = map(gen(3), function ($item, $key) { return "item {$key}: {$item}"; }); expect(iterator_to_array($actual))->toBe(['item 0: a', 'item 1: b', 'item 2: c']);
chunk
Return iterator of chunk iterators.
$actual = \iterator_to_array(map(chunk(gen(10), 3), '\\iterator_to_array')); expect($actual)->toBe([ ['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i'], ['j'] ]);