docs: added blank documentation

Author: andrepimpao

README.md

@@ -12,18 +12,12 @@ PHP validator with expressive error messages.
 
 ## Installation
 
-You can install the library via [Composer](https://getcomposer.org/):
+Install the library via [Composer](https://getcomposer.org/):
 
 ```bash
 composer require programmatordev/yet-another-php-validator
 ```
 
-To use the library, use Composer's [autoload](https://getcomposer.org/doc/01-basic-usage.md#autoloading):
-
-```php
-require_once 'vendor/autoload.php';
-```
-
 ## Basic Usage
 
 Simple usage looks like:

docs/01-get-started.md

@@ -10,18 +10,12 @@
 
 ## Installation
 
-You can install the library via [Composer](https://getcomposer.org/):
+Install the library via [Composer](https://getcomposer.org/):
 
 ```bash
 composer require programmatordev/yet-another-php-validator
 ```
 
-To use the library, use Composer's [autoload](https://getcomposer.org/doc/01-basic-usage.md#autoloading):
-
-```php
-require_once 'vendor/autoload.php';
-```
-
 ## Basic Usage
 
 Simple usage looks like:

docs/03-rules.md

@@ -10,6 +10,7 @@
 
 ## Basic Rules
 
+- [Blank](03-rules_blank.md)
 - [Count](03-rules_count.md)
 - [NotBlank](03-rules_not-blank.md)
 - [Type](03-rules_type.md)

docs/03-rules_blank.md

@@ -0,0 +1,56 @@
+# Blank
+
+Validates that a value is equal to an empty string, empty array, `false` or `null`.
+
+Check the [NotBlank](03-rules_not-blank.md) rule for the opposite validation.
+
+```php
+Blank(
+    ?callable $normalizer = null,
+    ?string $message = null
+);
+```
+
+## Basic Usage
+
+Bellow are the *only* cases where the rule will succeed by default, 
+everything else is considered invalid (you may want to check the [`normalizer`](#normalizer) option for a different behaviour):
+
+```php
+Validator::blank()->validate(''); // true
+Validator::blank()->validate([]); // true
+Validator::blank()->validate(false); // true
+Validator::blank()->validate(null); // true
+```
+
+## Options
+
+### `normalizer`
+
+type: `?callable` default: `null`
+
+Allows to define a `callable` that will be applied to the value before checking if it is valid.
+
+For example, use `trim`, or pass your own function, to not allow a string with whitespaces only:
+
+```php
+Validator::blank(normalizer: 'trim')->validate(' '); // true
+Validator::blank(normalizer: fn($value) => trim($value))->validate(' '); // true
+```
+
+### `message`
+
+type: `?string` default: `The {{ name }} value should be blank, {{ value }} given.`
+
+Message that will be shown if the value is not blank.
+
+The following parameters are available:
+
+| Parameter     | Description               |
+|---------------|---------------------------|
+| `{{ value }}` | The current invalid value |
+| `{{ name }}`  | Name of the invalid value |
+
+## Changelog
+
+- `1.2.0` Created

docs/03-rules_not-blank.md

@@ -2,6 +2,8 @@
 
 Validates that a value is not equal to a blank string, blank array, `false` or `null`.
 
+Check the [Blank](03-rules_blank.md) rule for the opposite validation.
+
 ```php
 NotBlank(
     ?callable $normalizer = null,
@@ -25,17 +27,14 @@ Validator::notBlank()->validate(null); // false
 
 ### `normalizer`
 
-type: `callable` default: `null`
+type: `?callable` default: `null`
 
 Allows to define a `callable` that will be applied to the value before checking if it is valid.
 
 For example, use `trim`, or pass your own function, to not allow a string with whitespaces only:
 
 ```php
-// Existing PHP callables
 Validator::notBlank(normalizer: 'trim')->validate(' '); // false
-
-// Function
 Validator::notBlank(normalizer: fn($value) => trim($value))->validate(' '); // false
 ```