chh / funk
A minimal functional programming library for PHP
Requires
- php: >=5.3.3
- chh/itertools: *@dev
This package is not auto-updated.
Last update: 2024-10-26 14:54:43 UTC
README
Funk is a minimal functional library for PHP.
It's a collection of some things, I've felt the need for in many projects:
- Dealing with Currying, memoizing and limiting calls to functions
(
Funk\Func
). - Common collection operators which deal in a uniform way with both
arrays and Iterators (
Funk\Collection
). - A tight wrapper around casting operations, which also deals with
casting objects to scalars (
Funk\Type
).
Install
Install with Composer:
php composer.phar require chh/funk:*@dev
Then require vendor/autoload.php
in your application.
Collection
The Funk\Collection
class wraps a PHP iterable value and provides
methods to manipulate it. The collection provides nearly all operations
using Iterators and exposes this iterator via getIterator
(also
implements IteratorAggregate
). That means that nearly all operations
are lazy evaluated.
You can see this in action, if you wrap a PDO statement in a collection
and then call map
. This wraps the PDO Statement in a special
"MappingIterator", which applies the callback function on each element
and yields the callback's return value. But this happens only when the
"MappingIterator" is iterated, until then nothing happens.
Example:
<?php use Funk\Collection, Funk\Collection\Operator as op; echo (new Collection(range(0, 20))) ->keep(function($x) { return $x > 5; }) ->remove(op::gt(7)) ->map(function($val) { return strval($val); }) ->join(' ');
Everywhere where the argument is predicate
the operation takes several
different values with different characteristics:
- An operator shortcut, which is an instance of the
Operator
class. Instances can be conveniently created by calling the operator as static method on this class. Valid operators include:is
,eq
,gt
,gte
,lt
andlte
. - Value, which is then compared against the current iterator's value by
using
===
. - Callback, the return value is used.
- Null, which translates to
$value == true
.
__construct($iterable = null)
dup()
extend($value)
append($value)
map($fn)
reduce($callback, $initial = null)
count()
match($pattern)
asArray($assoc = true)
slice($offset, $count = -1)
join($glue = '')
tap($callback, $arguments = array())
all($predicate = null)
some($predicate = null)
compact($callback = null)
attr($attribute)
item($offset)
invoke($method, $arguments = array())
isEmpty($predicate = null)
reverse()
keep($predicate)
remove($predicate)
Casting
Example:
<?php
use Funk\Type;
class Foo
{
function __toInt()
{
return 42;
}
}
echo Type::intval(new Foo) + 1;
# Output:
# 43