hash_equals(string $a, string $b) : boolean
Compares two strings using the same time whether they're equal or not.
Note: It can leak the length of a string when arguments of differing length are supplied.
This function was added in PHP 5.6. However, the Hash extension may be explicitly disabled on select servers. As of PHP 7.4.0, the Hash extension is a core PHP extension and can no longer be disabled. I.e. when PHP 7.4.0 becomes the minimum requirement, this polyfill can be safely removed.
package | PHP |
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since | 3.9.2 |
string
Expected string.
string
Actual, user supplied, string.
boolean
Whether strings are equal.is_countable(mixed $var) : boolean
Verify that the content of a variable is an array or an object implementing the Countable interface.
package | PHP |
---|---|
since | 4.9.6 |
mixed
The value to check.
boolean
True if `$var` is countable, false otherwise.is_iterable(mixed $var) : boolean
Verify that the content of a variable is an array or an object implementing the Traversable interface.
package | PHP |
---|---|
since | 4.9.6 |
mixed
The value to check.
boolean
True if `$var` is iterable, false otherwise.