iter

• Improve typehint for toArray() from array<T> to list<T>.

• Added iter\tap() function (https://github.com/nikic/iter/pull/95).

This release adds more precise phpdoc type annotations, using templates and specifying callable signatures (#93).

• Compatibility with PHP 8.1.

• Added iter\slice() method (#80). This works like explode() but produces an iterator.
• Added iter\mapWithKeys() method (#81). This works like iter\map() but also passes keys as second parameter to the callable.

This release makes iter compatible with PHP 7.4 by renaming the iter\fn namespace to iter\func.

• PHP >= 7.1 is now required. Functions are annotated with iterable types. (#52)
• The iter\fn namespace has been renamed to iter\func. This is necessary for PHP 7.4 compatibility. (#79)
• Default $preserveKeys = false in chunk() and add chunkWithKeys() function.
• Avoid advancing by one additional iteration in slice(). (#75)

• Added iter\enumerate() function (#43).
• Added iter\isEmpty() function (#46).
• Added $preserveKeys parameter to iter\chunk() (#42).

• Added $levels argument for flatten().
• Added flatMap() function.

• Fixed infinite loop when iter\zip() is called without arguments.
• Added additional error checks for various "length" and "count" parameters (usually disallowing negative numbers).
• The iter\flatten() function now preserves keys.
• Added an iter\recurse() function. Example use is iter\recurse('iter\toArray', $data) which will recursively convert an iterator to array.

• Added Iterator iter\product(...$iterables):
  Returns the cartesian product iterator of the passed iterators. (#25)
• Added bool iter\isIterable(mixed $value):
  Returns whether the value is an array or Traversable.
• Added $key parameter to the callback of reduce() and reductions(). (#28)
• Added support for <=> to fn\operator(). It is also supported on PHP versions that do not natively provide a <=> operator.
• All functions now validate that inputs are iterables.

• Added new iter functions:
  • mixed search(callable $predicate, iterable $iterable):
    Returns the first value from $iterable which satisfies $predicate, or null if no such element exists.
  • Iterator reductions(callable $function, iterable $iterable, mixed $startValue = null):
    Returns an iterator which contains the intermediate values produced by applying a reduction function to an iterator. Can for example be used to compute cumulative sums.
• Added support for the power operator (**) to iter\fn\operator(). Support is available also on older PHP versions which do not have an actual ** operator.

Added iter functions:

• Iterator mapKeys(callable $function, iterable $iterable)
• Iterator reindex(callable $function, iterable $iterable)
• Iterator chunk(iterable $iterable, int $size)
• Iterator flip(iterable $iterable)
• string join(string $separator, iterable $iterable)

Added iter\fn functions:

• function nested_index(...$indices)

First release :)