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syntax 
Helper Functions
****************

.[perex]
[api:Nette\Utils\Helpers] is a static class containing useful helper functions.


Installation:

```shell
composer require nette/utils
```

All examples assume the following class alias is defined:

```php
use Nette\Utils\Helpers;
```


capture(callable $func): string .[method]
-----------------------------------------

Executes a callback and returns the captured output as a string.

```php
$res = Helpers::capture(function () use ($template) {
	$template->render();
});
```


clamp(int|float $value, int|float $min, int|float $max): int|float .[method]
----------------------------------------------------------------------------

Clamps a value within the inclusive range specified by min and max.

```php
Helpers::clamp($level, 0, 255);
```


compare(mixed $left, string $operator, mixed $right): bool .[method]
--------------------------------------------------------------------

Compares two values the same way PHP does. It supports the operators `>`, `>=`, `<`, `<=`, `=`, `==`, `===`, `!=`, `!==`, `<>`. The function is useful in situations where the operator is determined dynamically (is a variable).

```php
Helpers::compare(10, '<', 20); // true
```


falseToNull(mixed $value): mixed .[method]
------------------------------------------

Converts `false` to `null`; other values remain unchanged.

```php
Helpers::falseToNull(false); // null
Helpers::falseToNull(123);   // 123
```


getLastError(): string .[method]
--------------------------------

Returns the last occurred PHP error or an empty string if no error occurred. Unlike `error_get_last()`, it's not affected by the PHP directive `html_errors` and always returns text, not HTML.

```php
Helpers::getLastError();
```


getSuggestion(string[] $possibilities, string $value): ?string .[method]
------------------------------------------------------------------------

From the given `$possibilities`, it finds the string most similar to `$value`, but not identical. It only supports 8-bit encodings.

This is useful when a certain option is invalid, and you want to suggest a similar alternative to the user (but a different one, which is why identical strings are ignored). This is how Nette generates the "did you mean ...?" messages.

```php
$items = ['foo', 'bar', 'baz'];
Helpers::getSuggestion($items, 'fo');   // 'foo'
Helpers::getSuggestion($items, 'barr'); // 'bar'
Helpers::getSuggestion($items, 'baz');  // 'bar', not 'baz'
```


splitClassName(string $name): array .[method]{data-version:4.0.10}
------------------------------------------------------------------

Splits a PHP class name into a namespace and a short class name. Returns an array of two strings where the first is the namespace and the second is the class name.

```php
Helpers::splitClassName('Nette\Utils\Helpers'); // ['Nette\Utils', 'Helpers']
Helpers::splitClassName('Foo');                 // ['', 'Foo']
```

{{maintitle: Nette Utils Helpers: clamp, compare, capture and More}}
{{description: Handy static helpers for PHP: capture output to a string, clamp a value to a range, compare values, get the last error and suggest the closest string.}}

Helper Functions

Nette\Utils\Helpers is a static class containing useful helper functions.

Installation:

composer require nette/utils

All examples assume the following class alias is defined:

use Nette\Utils\Helpers;

capture (callable $func): string

Executes a callback and returns the captured output as a string.

$res = Helpers::capture(function () use ($template) {
	$template->render();
});

clamp (int|float $value, int|float $min, int|float $max): int|float

Clamps a value within the inclusive range specified by min and max.

Helpers::clamp($level, 0, 255);

compare (mixed $left, string $operator, mixed $right): bool

Compares two values the same way PHP does. It supports the operators >, >=, <, <=, =, ==, ===, !=, !==, <>. The function is useful in situations where the operator is determined dynamically (is a variable).

Helpers::compare(10, '<', 20); // true

falseToNull (mixed $value): mixed

Converts false to null; other values remain unchanged.

Helpers::falseToNull(false); // null
Helpers::falseToNull(123);   // 123

getLastError(): string

Returns the last occurred PHP error or an empty string if no error occurred. Unlike error_get_last(), it's not affected by the PHP directive html_errors and always returns text, not HTML.

Helpers::getLastError();

getSuggestion (string[] $possibilities, string $value): ?string

From the given $possibilities, it finds the string most similar to $value, but not identical. It only supports 8-bit encodings.

This is useful when a certain option is invalid, and you want to suggest a similar alternative to the user (but a different one, which is why identical strings are ignored). This is how Nette generates the “did you mean …?” messages.

$items = ['foo', 'bar', 'baz'];
Helpers::getSuggestion($items, 'fo');   // 'foo'
Helpers::getSuggestion($items, 'barr'); // 'bar'
Helpers::getSuggestion($items, 'baz');  // 'bar', not 'baz'

splitClassName (string $name): array

Splits a PHP class name into a namespace and a short class name. Returns an array of two strings where the first is the namespace and the second is the class name.

Helpers::splitClassName('Nette\Utils\Helpers'); // ['Nette\Utils', 'Helpers']
Helpers::splitClassName('Foo');                 // ['', 'Foo']