Built-in rules

The library contains a minimal number of useful rules.

String

The string() method applies a built-in rule that verifies a value if the value type is string.

Example:

import v9s from 'v9s';

const check = v9s.string().check;

console.log(check('42')); // true
console.log(check(42)); // false

Number

The number() method applies a built-in rule that verifies a value if the value type is number.

Example:

import v9s from 'v9s';

const check = v9s.number().check;

console.log(check(42)); // true
console.log(check('42')); // false

Boolean

The boolean() method applies a built-in rule that verifies a value if the value type is boolean.

Example:

import v9s from 'v9s';

const check = v9s.boolean().check;

console.log(check(true)); // true
console.log(check(42)); // false

Object

The object() method applies a built-in rule that verifies a value if the value type is object and the value is not null.

Example:

import v9s from 'v9s';

const check = v9s.object().check;

console.log(check({})); // true
console.log(check(null)); // false
console.log(check(42)); // false

Null

The null() method applies a built-in rule that verifies a value if the value is null.

Example:

import v9s from 'v9s';

const check = v9s.null().check;

console.log(check(null)); // true
console.log(check({})); // false
console.log(check(42)); // false

Defined

The defined() method applies a built-in rule that verifies a value if the value is not undefined.

Example:

import v9s from 'v9s';

const check = v9s.defined().check;

console.log(check(42)); // true
console.log(check(null)); // true
console.log(check(undefined)); // false

Not defined

The notDefined() method applies a built-in rule that verifies a value if the value is undefined.

Example:

import v9s from 'v9s';

const check = v9s.notDefined().check;

console.log(check(undefined)); // true
console.log(check(42)); // false
console.log(check(null)); // false

None

The none() method applies a built-in rule that verifies a value if the value is null or undefined.

Example:

import v9s from 'v9s';

const check = v9s.none().check;

console.log(check(undefined)); // true
console.log(check(null)); // true
console.log(check(42)); // false

Not none

The notNone() method applies a built-in rule that verifies a value if the value is not null or undefined.

Example:

import v9s from 'v9s';

const check = v9s.none().check;

console.log(check(42)); // true
console.log(check(undefined)); // false
console.log(check(null)); // false

Equal

The eq() method applies a built-in rule that verifies a value if the value is equal to the referenced value.

Example:

import v9s from 'v9s';

const check = v9s.eq(42).check;

console.log(check(42)); // true
console.log(check(43)); // false
console.log(check('42')); // false

Not Equal

The ne() method applies a built-in rule that verifies a value if the value is not equal to the referenced value.

Example:

import v9s from 'v9s';

const check = v9s.ne(42).check;

console.log(check(43)); // true
console.log(check('42')); // true
console.log(check(42)); // false

Greater

The gt() method applies a built-in rule that verifies a value if the value is greater than the threshold.

Example:

import v9s from 'v9s';

const check = v9s.gt(42).check;

console.log(check(43)); // true
console.log(check(42)); // false

Greater or equal

The gte() method applies a built-in rule that verifies a value if the value is greater than or equal to the threshold.

Example:

import v9s from 'v9s';

const check = v9s.gte(42).check;

console.log(check(43)); // true
console.log(check(42)); // true
console.log(check(41)); // false

Less

The lt() method applies a built-in rule that verifies a value if the value is less than the threshold.

Example:

import v9s from 'v9s';

const check = v9s.lt(42).check;

console.log(check(41)); // true
console.log(check(42)); // false

Less or equal

The lte() method applies a built-in rule that verifies a value if the value is less than or equal to the threshold.

Example:

import v9s from 'v9s';

const check = v9s.lte(42).check;

console.log(check(41)); // true
console.log(check(42)); // true
console.log(check(43)); // false

Between

The between() method applies a built-in rule that verifies a value if the value is between minimum and maximum reference values, inclusive.

Example:

import v9s from 'v9s';

const check = v9s.between(10, 100).check;

console.log(check(10)); // true
console.log(check(50)); // true
console.log(check(9)); // false
console.log(check(101)); // false

Minimum length

The minLength() method applies a built-in rule that verifies a value if the value length is greater than or equal to the specified minimum length.

Example:

import v9s from 'v9s';

const check = v9s.minLength(5).check;

console.log(check('halo')); // false
console.log(check('hello')); // true
console.log(check('hello, world')); // true
console.log(check([0, 1, 2, 3, 4])); // true

Maximum length

The maxLength() method applies a built-in rule that verifies a value if the value length is less than or equal to the specified minimum length.

Example:

import v9s from 'v9s';

const check = v9s.minLength(5).check;

console.log(check('halo')); // true
console.log(check('hello')); // true
console.log(check('hello, world')); // false
console.log(check([0, 1, 2, 3, 4])); // true

Strict length

The strictLength() method applies a built-in rule that verifies a value if the value length is less than or equal to the specified minimum length.

Example:

import v9s from 'v9s';

const check = v9s.strictLength(5).check;

console.log(check('halo')); // false
console.log(check('hello')); // true
console.log(check('hello, world')); // false
console.log(check([0, 1, 2, 3, 4])); // true

Length between

The lengthBetween() method applies a built-in rule that verifies a value if the value length is between minimum and maximum lengths, inclusive.

Example:

import v9s from 'v9s';

const check = v9s.lengthBetween(5, 12).check;

console.log(check('halo')); // false
console.log(check('hello')); // true
console.log(check('hello, world')); // true
console.log(check([0, 1, 2, 3, 4])); // true