Allow object keys

[simPod]

WDYT about this? Currently only array-key is supported as key type for all functions.

[codecov]

Codecov Report

Merging #24 (7e8f271) into 2.0.x-dev (5d1b992) will not change coverage.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           2.0.x-dev       #24   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
===========================================
  Files              2         2           
  Lines             43        43           
===========================================
  Hits              43        43           

Impacted Files	Coverage Δ
src/iterable-functions.php	100.00% <100.00%> (ø)

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[bpolaszek]

Yeah, definitely 🙂

[simPod]

So I can edit other functions too. However, this restricts only one read of output iterable as the value is of type Generator

I'm used to it as I use generators extensively but don't have overview out of my bubble.

[bpolaszek]

Indeed, forgot that. I have a fix in mind.

[bpolaszek]

Well, here's the fix I was thinking about:

function iterable_map(iterable $iterable, callable $map): iterable
{
    return new class ($iterable, $map) implements IteratorAggregate {
        private $iterable;
        private $map;

        public function __construct(iterable $iterable, callable $map)
        {
            $this->iterable = $iterable;
            $this->map = $map;
        }

        public function getIterator(): Traversable
        {
            foreach ($this->iterable as $key => $item) {
                yield $key => ($this->map)($item);
            }
        }
    };
}

It works, but basically this anonymous class is exactly what IterableObject already does. Problem: IterableObject calls iterable_map itself, so if we use it directly, we're going into spaghetti code.

What we could do is a refactoring, where functions would just be shortcuts to IterableObject::* methods (meaning we move map / filter logic into IterableObject methods), instead of the opposite:

function iterable_map(iterable $iterable, callable $map): iterable
{
    return iterable($iterable)->map($map);
}

WDYT?

[simPod]

Ah yes, we simply have to leverage IteratorAggregate and we're good to go.

[bpolaszek]

OK, I will perform the refactoring as soon as #25 is merged.