zip()

Iterates over two streaming sources in parallel, yielding pairs of keys and values from both sources.

There are three modes of operation:

  • strict - Iteration continues until the first source is depleted. If the second source is depleted before the first, an exception is thrown.

  • longest - Iteration continues until both sources are depleted. If one source is depleted before the other, null is yielded for the missing values.

  • shortest - Iteration continues until the first source is depleted. If one source is depleted before the other, iteration stops.

Attention

For each mode, there is also a corresponding operator: `zipStrict()`, `zipLongest()` and `zipShortest()` which can be used instead of zip() operator with mode parameter. Those operators better describe return type for codebases using PHPStan or Psalm static analysis tools.

class RunOpenCode\Component\Dataset\Operator\Zip
__construct(iterable<TKey1, TValue1> $first, iterable<TKey2, TValue2> $second, string $mode = 'strict')
Parameters:

  • $first – iterable<TKey1, TValue1> First stream source to iterate over.

  • $second – iterable<TKey2, TValue2> Second stream source to iterate over.

  • $mode – string Mode of operation (‘strict’, ‘longest’, ‘shortest’).

getIterator()
Returns:

\Traversable<array{TKey1|null, TKey2|null}, array{TValue1|null, TValue2|null}> Items from the stream sources yielded in pairs of keys and values.

Use cases

  • Combining two streams into one stream of pairs of keys and values.

Example

1<?php
2
3use RunOpenCode\Component\Dataset\Stream;
4
5new Stream(['Bob', 'Alice', 'John'])
6      ->zip(['Smith', 'Johnson', 'Doe']); // yields ['Bob', 'Smith'], ['Alice', 'Johnson'], ['John', 'Doe']