A curated collection of useful PHP snippets that you can understand in 30 seconds or less.
Note: This project is inspired by 30 Seconds of Code, but there is no affiliation with that project.
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Returns true if the provided function returns true for all elements of an array, false otherwise.
function all($items, $func)
{
return count(array_filter($items, $func)) === count($items);
}Examples
all([2, 3, 4, 5], function ($item) {
return $item > 1;
}); // trueReturns true if the provided function returns true for at least one element of an array, false otherwise.
function any($items, $func)
{
return count(array_filter($items, $func)) > 0;
}Examples
any([1, 2, 3, 4], function ($item) {
return $item < 2;
}); // trueDeep flattens an array.
function deepFlatten($items)
{
$result = [];
foreach ($items as $item) {
if (!is_array($item)) {
$result[] = $item;
} else {
$result = array_merge($result, deepFlatten($item));
}
}
return $result;
}Examples
deepFlatten([1, [2], [[3], 4], 5]); // [1, 2, 3, 4, 5]Returns a new array with n elements removed from the left.
function drop($items, $n = 1)
{
return array_slice($items, $n);
}Examples
drop([1, 2, 3]); // [2,3]
drop([1, 2, 3], 2); // [3]Returns the last element for which the provided function returns a truthy value.
function findLast($items, $func)
{
$filteredItems = array_filter($items, $func);
return array_pop($filteredItems);
}Examples
findLast([1, 2, 3, 4], function ($n) {
return ($n % 2) === 1;
});
// 3Returns the index of the last element for which the provided function returns a truthy value.
function findLastIndex($items, $func)
{
$keys = array_keys(array_filter($items, $func));
return array_pop($keys);
}Examples
findLastIndex([1, 2, 3, 4], function ($n) {
return ($n % 2) === 1;
});
// 2Flattens an array up to the one level depth.
function flatten($items)
{
$result = [];
foreach ($items as $item) {
if (!is_array($item)) {
$result[] = $item;
} else {
$result = array_merge($result, array_values($item));
}
}
return $result;
}Examples
flatten([1, [2], 3, 4]); // [1, 2, 3, 4]Groups the elements of an array based on the given function.
function groupBy($items, $func)
{
$group = [];
foreach ($items as $item) {
if ((!is_string($func) && is_callable($func)) || function_exists($func)) {
$key = call_user_func($func, $item);
$group[$key][] = $item;
} elseif (is_object($item)) {
$group[$item->{$func}][] = $item;
} elseif (isset($item[$func])) {
$group[$item[$func]][] = $item;
}
}
return $group;
}Examples
groupBy(['one', 'two', 'three'], 'strlen'); // [3 => ['one', 'two'], 5 => ['three']]Checks a flat list for duplicate values. Returns true if duplicate values exists and false if values are all unique.
function hasDuplicates($items)
{
return count($items) > count(array_unique($items));
}Examples
hasDuplicates([1, 2, 3, 4, 5, 5]); // trueReturns the head of a list.
function head($items)
{
return reset($items);
}Examples
head([1, 2, 3]); // 1Returns the last element in an array.
function last($items)
{
return end($items);
}Examples
last([1, 2, 3]); // 3Retrieves all of the values for a given key:
function pluck($items, $key)
{
return array_map( function($item) use ($key) {
return is_object($item) ? $item->$key : $item[$key];
}, $items);
}Examples
pluck([
['product_id' => 'prod-100', 'name' => 'Desk'],
['product_id' => 'prod-200', 'name' => 'Chair'],
], 'name');
// ['Desk', 'Chair']Mutates the original array to filter out the values specified.
function pull(&$items, ...$params)
{
$items = array_values(array_diff($items, $params));
return $items;
}Examples
$items = ['a', 'b', 'c', 'a', 'b', 'c'];
pull($items, 'a', 'c'); // $items will be ['b', 'b']Filters the collection using the given callback.
function reject($items, $func)
{
return array_values(array_diff($items, array_filter($items, $func)));
}Examples
reject(['Apple', 'Pear', 'Kiwi', 'Banana'], function ($item) {
return strlen($item) > 4;
}); // ['Pear', 'Kiwi']Removes elements from an array for which the given function returns false.
function remove($items, $func)
{
$filtered = array_filter($items, $func);
return array_diff_key($items, $filtered);
}Examples
remove([1, 2, 3, 4], function ($n) {
return ($n % 2) === 0;
});
// [0 => 1, 2 => 3]Returns all elements in an array except for the first one.
function tail($items)
{
return count($items) > 1 ? array_slice($items, 1) : $items;
}Examples
tail([1, 2, 3]); // [2, 3]Returns an array with n elements removed from the beginning.
function take($items, $n = 1)
{
return array_slice($items, 0, $n);
}Examples
take([1, 2, 3], 5); // [1, 2, 3]
take([1, 2, 3, 4, 5], 2); // [1, 2]Filters out the elements of an array, that have one of the specified values.
function without($items, ...$params)
{
return array_values(array_diff($items, $params));
}Examples
without([2, 1, 2, 3], 1, 2); // [3]Sorts a collection of arrays or objects by key.
function orderBy($items, $attr, $order)
{
$sortedItems = [];
foreach ($items as $item) {
$key = is_object($item) ? $item->{$attr} : $item[$attr];
$sortedItems[$key] = $item;
}
if ($order === 'desc') {
krsort($sortedItems);
} else {
ksort($sortedItems);
}
return array_values($sortedItems);
}Examples
orderBy(
[
['id' => 2, 'name' => 'Joy'],
['id' => 3, 'name' => 'Khaja'],
['id' => 1, 'name' => 'Raja']
],
'id',
'desc'
); // [['id' => 3, 'name' => 'Khaja'], ['id' => 2, 'name' => 'Joy'], ['id' => 1, 'name' => 'Raja']]Returns the average of two or more numbers.
function average(...$items)
{
$count = count($items);
return $count === 0 ? 0 : array_sum($items) / $count;
}Examples
average(1, 2, 3); // 2Calculates the factorial of a number.
function factorial($n)
{
if ($n <= 1) {
return 1;
}
return $n * factorial($n - 1);
}Examples
factorial(6); // 720Generates an array, containing the Fibonacci sequence, up until the nth term.
function fibonacci($n)
{
$sequence = [0, 1];
for ($i = 2; $i < $n; $i++) {
$sequence[$i] = $sequence[$i-1] + $sequence[$i-2];
}
return $sequence;
}Examples
fibonacci(6); // [0, 1, 1, 2, 3, 5]Calculates the greatest common divisor between two or more numbers.
function gcd(...$numbers)
{
if (count($numbers) > 2) {
return array_reduce($numbers, 'gcd');
}
$r = $numbers[0] % $numbers[1];
return $r === 0 ? abs($numbers[1]) : gcd($numbers[1], $r);
}Examples
gcd(8, 36); // 4
gcd(12, 8, 32); // 4Returns true if the given number is even, false otherwise.
function isEven($number)
{
return ($number % 2) === 0;
}Examples
isEven(4); // trueChecks if the provided integer is a prime number.
function isPrime($number)
{
$boundary = floor(sqrt($number));
for ($i = 2; $i <= $boundary; $i++) {
if ($number % $i === 0) {
return false;
}
}
return $number >= 2;
}Examples
isPrime(3); // trueReturns the least common multiple of two or more numbers.
function lcm(...$numbers)
{
$ans = $numbers[0];
for ($i = 1, $max = count($numbers); $i < $max; $i++) {
$ans = (($numbers[$i] * $ans) / gcd($numbers[$i], $ans));
}
return $ans;
}Examples
lcm(12, 7); // 84
lcm(1, 3, 4, 5); // 60Returns the median of an array of numbers.
function median($numbers)
{
sort($numbers);
$totalNumbers = count($numbers);
$mid = floor($totalNumbers / 2);
return ($totalNumbers % 2) === 0 ? ($numbers[$mid - 1] + $numbers[$mid]) / 2 : $numbers[$mid];
}Examples
median([1, 3, 3, 6, 7, 8, 9]); // 6
median([1, 2, 3, 6, 7, 9]); // 4.5Returns the n maximum elements from the provided array.
function maxN($numbers)
{
$maxValue = max($numbers);
$maxValueArray = array_filter($numbers, function ($value) use ($maxValue) {
return $maxValue === $value;
});
return count($maxValueArray);
}Examples
maxN([1, 2, 3, 4, 5, 5]); // 2
maxN([1, 2, 3, 4, 5]); // 1Returns the n minimum elements from the provided array.
function minN($numbers)
{
$minValue = min($numbers);
$minValueArray = array_filter($numbers, function ($value) use ($minValue) {
return $minValue === $value;
});
return count($minValueArray);
}Examples
minN([1, 1, 2, 3, 4, 5, 5]); // 2
minN([1, 2, 3, 4, 5]); // 1Checks if two numbers are approximately equal to each other.
Use abs() to compare the absolute difference of the two values to epsilon. Omit the third parameter, epsilon, to use a default value of 0.001.
function approximatelyEqual($number1, $number2, $epsilon = 0.001)
{
return abs($number1 - $number2) < $epsilon;
}Examples
approximatelyEqual(10.0, 10.00001); // true
approximatelyEqual(10.0, 10.01); // falseClamps num within the inclusive range specified by the boundary values a and b.
If num falls within the range, return num. Otherwise, return the nearest number in the range.
function clampNumber($num, $a, $b)
{
return max(min($num, max($a, $b)), min($a, $b));
}Examples
clampNumber(2, 3, 5); // 3
clampNumber(1, -1, -5); // -1Check if a string is ends with a given substring.
function endsWith($haystack, $needle)
{
return strrpos($haystack, $needle) === (strlen($haystack) - strlen($needle));
}Examples
endsWith('Hi, this is me', 'me'); // trueReturns the first string there is between the strings from the parameter start and end.
function firstStringBetween($haystack, $start, $end)
{
return trim(strstr(strstr($haystack, $start), $end, true), $start . $end);
}Examples
firstStringBetween('This is a [custom] string', '[', ']'); // customCompare two strings and returns true if both strings are anagram, false otherwise.
function isAnagram($string1, $string2)
{
return count_chars($string1, 1) === count_chars($string2, 1);
}Examples
isAnagram('act', 'cat'); // trueReturns true if the given string is lower case, false otherwise.
function isLowerCase($string)
{
return $string === strtolower($string);
}Examples
isLowerCase('Morning shows the day!'); // false
isLowerCase('hello'); // trueReturns true if the given string is upper case, false otherwise.
function isUpperCase($string)
{
return $string === strtoupper($string);
}Examples
isUpperCase('MORNING SHOWS THE DAY!'); // true
isUpperCase('qUick Fox'); // falseReturns true if the given string is a palindrome, false otherwise.
function palindrome($string)
{
return strrev($string) === (string) $string;
}Examples
palindrome('racecar'); // true
palindrome(2221222); // trueCheck if a string starts with a given substring.
function startsWith($haystack, $needle)
{
return strpos($haystack, $needle) === 0;
}Examples
startsWith('Hi, this is me', 'Hi'); // trueReturns number of vowels in provided string.
Use a regular expression to count the number of vowels (A, E, I, O, U) in a string.
function countVowels($string)
{
preg_match_all('/[aeiou]/i', $string, $matches);
return count($matches[0]);
}Examples
countVowels('sampleInput'); // 4Decapitalizes the first letter of a string.
Decapitalizes the first letter of the string and then adds it with rest of the string. Omit the upperRest parameter to keep the rest of the string intact, or set it to true to convert to uppercase.
function decapitalize($string, $upperRest = false)
{
return lcfirst($upperRest ? strtoupper($string) : $string);
}Examples
decapitalize('FooBar'); // 'fooBar'Check if a word / substring exist in a given string input.
Using strpos to find the position of the first occurrence of a substring in a string. Returns either true or false
function isContains($string, $needle)
{
return strpos($string, $needle);
}Examples
isContains('This is an example string', 'example'); // trueisContains('This is an example string', 'hello'); // falseReturn a new function that composes multiple functions into a single callable.
function compose(...$functions)
{
return array_reduce(
$functions,
function ($carry, $function) {
return function ($x) use ($carry, $function) {
return $function($carry($x));
};
},
function ($x) {
return $x;
}
);
}Examples
$compose = compose(
// add 2
function ($x) {
return $x + 2;
},
// multiply 4
function ($x) {
return $x * 4;
}
);
$compose(3); // 20Memoization of a function results in memory.
function memoize($func)
{
return function () use ($func) {
static $cache = [];
$args = func_get_args();
$key = serialize($args);
$cached = true;
if (!isset($cache[$key])) {
$cache[$key] = $func(...$args);
$cached = false;
}
return ['result' => $cache[$key], 'cached' => $cached];
};
}Examples
$memoizedAdd = memoize(
function ($num) {
return $num + 10;
}
);
var_dump($memoizedAdd(5)); // ['result' => 15, 'cached' => false]
var_dump($memoizedAdd(6)); // ['result' => 16, 'cached' => false]
var_dump($memoizedAdd(5)); // ['result' => 15, 'cached' => true]Curries a function to take arguments in multiple calls.
function curry($function)
{
$accumulator = function ($arguments) use ($function, &$accumulator) {
return function (...$args) use ($function, $arguments, $accumulator) {
$arguments = array_merge($arguments, $args);
$reflection = new ReflectionFunction($function);
$totalArguments = $reflection->getNumberOfRequiredParameters();
if ($totalArguments <= count($arguments)) {
return $function(...$arguments);
}
return $accumulator($arguments);
};
};
return $accumulator([]);
}Examples
$curriedAdd = curry(
function ($a, $b) {
return $a + $b;
}
);
$add10 = $curriedAdd(10);
var_dump($add10(15)); // 25Call a function only once.
function once($function)
{
return function (...$args) use ($function) {
static $called = false;
if ($called) {
return;
}
$called = true;
return $function(...$args);
};
}Examples
$add = function ($a, $b) {
return $a + $b;
};
$once = once($add);
var_dump($once(10, 5)); // 15
var_dump($once(20, 10)); // nullVariadic functions allows you to capture a variable number of arguments to a function.
The function accepts any number of variables to execute the code. It uses a for loop to iterate over the parameters.
function variadicFunction($operands)
{
$sum = 0;
foreach($operands as $singleOperand) {
$sum += $singleOperand;
}
return $sum;
}Examples
variadicFunction([1, 2]); // 3
variadicFunction([1, 2, 3, 4]); // 10You're always welcome to contribute to this project. Please read the contribution guide.
This project is licensed under the MIT License - see the License File for details