use function nspl\f\compose;
use function nspl\f\memoized;
use const nspl\op\object;
use const nspl\op\gt;
use const nspl\op\mul;
use function nspl\op\propertyGetter;
use const nspl\a\value;
use function nspl\a\map;
use function nspl\a\reduce;
use function nspl\a\filter;
$users = map(object, [array('id' => 1, 'name' => 'John', 'age' => 15), array('id' => 2, 'name' => 'Jack', 'age' => 35), array('id' => 3, 'name' => 'Sarah', 'age' => 25), array('id' => 4, 'name' => 'Norah', 'age' => 20), array('id' => 5, 'name' => 'Michael', 'age' => 30), array('id' => 6, 'name' => 'Bob', 'age' => 30)]);
// 1. Get user name from which can be stored as username, user_name or name in data array
$data = array('id' => 1337, 'name' => 'John', 'gender' => 'male');
$name = reduce(flipped(partial(value, $data)), ['username', 'user_name', 'name'], '');
echo sprintf("User name is %s\n", $name);
// 2. Get users older than 25
$isOlderThan25 = compose(rpartial(gt, 25), propertyGetter('age'));
$olderThan25 = filter($isOlderThan25, $users);
echo "These users are older than 25:\n";
foreach ($olderThan25 as $user) {
echo sprintf(" %s - %s y.o.\n", $user->name, $user->age);
}
// 3. Memoizing heavy calculations
$factorial = function ($n) {
echo "Calculating {$n}!\n";
return reduce(mul, range(1, $n), 1);
};
$memoizedFactorial = memoized($factorial);
foreach ([3, 3, 5, 5, 5] as $n) {
echo sprintf("%s! = %s\n", $n, $memoizedFactorial($n));
}
public function testMemoized()
{
$calculationsPerformed = 0;
$f = function ($arg1, $arg2) use(&$calculationsPerformed) {
++$calculationsPerformed;
return $arg1;
};
$object = (object) array('name' => 'Hello wordl', 'answer' => 42);
$memoized = memoized($f);
$result = $memoized(1, 'a');
$this->assertEquals(1, $result);
$this->assertEquals(1, $calculationsPerformed);
$result = $memoized(1, 'a');
$this->assertEquals(1, $result);
$this->assertEquals(1, $calculationsPerformed);
$result = $memoized(1, ['b']);
$result = $memoized(1, ['b']);
$this->assertEquals(1, $result);
$this->assertEquals(2, $calculationsPerformed);
$result = $memoized(null, ['b']);
$result = $memoized(null, ['b']);
$this->assertEquals(null, $result);
$this->assertEquals(3, $calculationsPerformed);
$result = $memoized($object, true);
$result = $memoized($object, true);
$this->assertEquals($object, $result);
$this->assertEquals(4, $calculationsPerformed);
$calculationsPerformed = 0;
$memoized = call_user_func(memoized, $f);
$result = $memoized(1, 'a');
$this->assertEquals(1, $result);
$this->assertEquals(1, $calculationsPerformed);
$result = $memoized(1, 'a');
$this->assertEquals(1, $result);
$this->assertEquals(1, $calculationsPerformed);
$result = $memoized(1, ['b']);
$result = $memoized(1, ['b']);
$this->assertEquals(1, $result);
$this->assertEquals(2, $calculationsPerformed);
$result = $memoized(null, ['b']);
$result = $memoized(null, ['b']);
$this->assertEquals(null, $result);
$this->assertEquals(3, $calculationsPerformed);
$result = $memoized($object, true);
$result = $memoized($object, true);
$this->assertEquals($object, $result);
$this->assertEquals(4, $calculationsPerformed);
$this->assertEquals('\\nspl\\f\\memoized', memoized);
}