/**
* Takes "a|b[]|c|d[]|e" and returns "b|d"
*
* @return UnionType
* The subset of types in this
*/
public function genericArrayElementTypes() : UnionType
{
// If array is in there, then it can be any type
// Same for mixed
if ($this->hasType(ArrayType::instance()) || $this->hasType(MixedType::instance())) {
return MixedType::instance()->asUnionType();
}
if ($this->hasType(ArrayType::instance())) {
return NullType::instance()->asUnionType();
}
return new UnionType($this->type_set->filter(function (Type $type) : bool {
return $type->isGenericArray();
})->map(function (Type $type) : Type {
return $type->genericArrayElementType();
}));
}
