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isntnt - npm Package Compare versions

Comparing version 2.0.0-beta.0 to 2.0.0-beta.1

dist/esm/lib/predicates/hasLength.d.ts
dist/esm/lib/predicates/hasLength.js
dist/esm/lib/predicates/hasLength.js.map
dist/lib/predicates/hasLength.d.ts
dist/lib/predicates/hasLength.js
dist/lib/predicates/hasLength.js.map
src/lib/predicates/hasLength.ts

3

dist/esm/lib/predicates.d.ts

@@ -0,1 +1,2 @@

export { hasLength } from './predicates/hasLength';
export { isAny } from './predicates/isAny';

@@ -43,2 +44,2 @@ export { isArray } from './predicates/isArray';

export { isWeakMap } from './predicates/isWeakMap';
export { hasLength as isWithLength } from './predicates/isWithLength';
export { isWithLength } from './predicates/isWithLength';

3

dist/esm/lib/predicates.js

@@ -0,1 +1,2 @@

export { hasLength } from './predicates/hasLength';
export { isAny } from './predicates/isAny';

@@ -43,3 +44,3 @@ export { isArray } from './predicates/isArray';

export { isWeakMap } from './predicates/isWeakMap';
export { hasLength as isWithLength } from './predicates/isWithLength';
export { isWithLength } from './predicates/isWithLength';
//# sourceMappingURL=predicates.js.map

5

dist/esm/lib/predicates/isArrayLike.js
import { and } from '../generics/and';
import { at } from '../generics/at';
import { isFunction } from './isFunction';
import { isLength } from './isLength';
export const isArrayLike = and(at('length', isLength), (value) => !isFunction(value));
import { hasLength } from './hasLength';
export const isArrayLike = and(hasLength, (value) => !isFunction(value));
//# sourceMappingURL=isArrayLike.js.map

3

dist/esm/lib/predicates/isWithLength.d.ts

@@ -1,3 +0,4 @@

export declare const hasLength: import("../types").Predicate<{
/** @deprecated */
export declare const isWithLength: import("../types").Predicate<{
length: number;
}>;

3

dist/esm/lib/predicates/isWithLength.js
import { at } from '../generics/at';
import { isLength } from './isLength';
export const hasLength = at('length', isLength);
/** @deprecated */
export const isWithLength = at('length', isLength);
//# sourceMappingURL=isWithLength.js.map

13

dist/esm/lib/types.d.ts

@@ -1,10 +0,1 @@

export declare type InferredPartial<T extends {}> = {
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? K : never;
}[keyof T]]: InferredPartial<T[P]>;
} & Partial<{
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? never : K;
}[keyof T]]: InferredPartial<T[P]>;
}>;
export declare type Predicate<T> = <U>(value: U) => value is Extract<U, T>;

@@ -26,5 +17,3 @@ export declare type Static<T extends Predicate<any>> = T extends Predicate<infer R> ? R : never;

};
export declare type ObjectLike = {
[P in PropertyKey]: unknown;
};
export declare type ObjectLike = Exclude<Some, boolean>;
export declare type Primitive = SerializablePrimitive | undefined | symbol | bigint;

@@ -31,0 +20,0 @@ export declare type SerializableArray = Array<Serializable> | ReadonlyArray<Serializable>;

3

dist/lib/predicates.d.ts

@@ -0,1 +1,2 @@

export { hasLength } from './predicates/hasLength';
export { isAny } from './predicates/isAny';

@@ -43,2 +44,2 @@ export { isArray } from './predicates/isArray';

export { isWeakMap } from './predicates/isWeakMap';
export { hasLength as isWithLength } from './predicates/isWithLength';
export { isWithLength } from './predicates/isWithLength';

6

dist/lib/predicates.js
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.isWithLength = exports.isWeakMap = exports.isUndefined = exports.isUint32 = exports.isUint16 = exports.isUint8 = exports.isUint = exports.isTrue = exports.isSymbol = exports.isString = exports.isSome = exports.isSet = exports.isSerializablePrimitive = exports.isSerializableObject = exports.isSerializableNumber = exports.isSerializableArray = exports.isSerializable = exports.isRegExp = exports.isPrimitive = exports.isPositive = exports.isPlainObject = exports.isObjectLike = exports.isObject = exports.isNumber = exports.isNull = exports.isNone = exports.isNever = exports.isNegative = exports.isMap = exports.isLength = exports.isInt32 = exports.isInt16 = exports.isInt8 = exports.isInt = exports.isFunction = exports.isFalse = exports.isDictionary = exports.isDate = exports.isBoolean = exports.isBigInt = exports.isArrayLike = exports.isArray = exports.isAny = void 0;
exports.isWithLength = exports.isWeakMap = exports.isUndefined = exports.isUint32 = exports.isUint16 = exports.isUint8 = exports.isUint = exports.isTrue = exports.isSymbol = exports.isString = exports.isSome = exports.isSet = exports.isSerializablePrimitive = exports.isSerializableObject = exports.isSerializableNumber = exports.isSerializableArray = exports.isSerializable = exports.isRegExp = exports.isPrimitive = exports.isPositive = exports.isPlainObject = exports.isObjectLike = exports.isObject = exports.isNumber = exports.isNull = exports.isNone = exports.isNever = exports.isNegative = exports.isMap = exports.isLength = exports.isInt32 = exports.isInt16 = exports.isInt8 = exports.isInt = exports.isFunction = exports.isFalse = exports.isDictionary = exports.isDate = exports.isBoolean = exports.isBigInt = exports.isArrayLike = exports.isArray = exports.isAny = exports.hasLength = void 0;
var hasLength_1 = require("./predicates/hasLength");
Object.defineProperty(exports, "hasLength", { enumerable: true, get: function () { return hasLength_1.hasLength; } });
var isAny_1 = require("./predicates/isAny");

@@ -89,3 +91,3 @@ Object.defineProperty(exports, "isAny", { enumerable: true, get: function () { return isAny_1.isAny; } });

var isWithLength_1 = require("./predicates/isWithLength");
Object.defineProperty(exports, "isWithLength", { enumerable: true, get: function () { return isWithLength_1.hasLength; } });
Object.defineProperty(exports, "isWithLength", { enumerable: true, get: function () { return isWithLength_1.isWithLength; } });
//# sourceMappingURL=predicates.js.map

5

dist/lib/predicates/isArrayLike.js

@@ -5,6 +5,5 @@ "use strict";

const and_1 = require("../generics/and");
const at_1 = require("../generics/at");
const isFunction_1 = require("./isFunction");
const isLength_1 = require("./isLength");
exports.isArrayLike = and_1.and(at_1.at('length', isLength_1.isLength), (value) => !isFunction_1.isFunction(value));
const hasLength_1 = require("./hasLength");
exports.isArrayLike = and_1.and(hasLength_1.hasLength, (value) => !isFunction_1.isFunction(value));
//# sourceMappingURL=isArrayLike.js.map

3

dist/lib/predicates/isWithLength.d.ts

@@ -1,3 +0,4 @@

export declare const hasLength: import("../types").Predicate<{
/** @deprecated */
export declare const isWithLength: import("../types").Predicate<{
length: number;
}>;

5

dist/lib/predicates/isWithLength.js
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.hasLength = void 0;
exports.isWithLength = void 0;
const at_1 = require("../generics/at");
const isLength_1 = require("./isLength");
exports.hasLength = at_1.at('length', isLength_1.isLength);
/** @deprecated */
exports.isWithLength = at_1.at('length', isLength_1.isLength);
//# sourceMappingURL=isWithLength.js.map

13

dist/lib/types.d.ts

@@ -1,10 +0,1 @@

export declare type InferredPartial<T extends {}> = {
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? K : never;
}[keyof T]]: InferredPartial<T[P]>;
} & Partial<{
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? never : K;
}[keyof T]]: InferredPartial<T[P]>;
}>;
export declare type Predicate<T> = <U>(value: U) => value is Extract<U, T>;

@@ -26,5 +17,3 @@ export declare type Static<T extends Predicate<any>> = T extends Predicate<infer R> ? R : never;

};
export declare type ObjectLike = {
[P in PropertyKey]: unknown;
};
export declare type ObjectLike = Exclude<Some, boolean>;
export declare type Primitive = SerializablePrimitive | undefined | symbol | bigint;

@@ -31,0 +20,0 @@ export declare type SerializableArray = Array<Serializable> | ReadonlyArray<Serializable>;

2

package.json
{
"name": "isntnt",
"version": "2.0.0-beta.0",
"version": "2.0.0-beta.1",
"description": "A collection of composable JavaScript runtime type predicates with TypeScript type guard declarations",

@@ -5,0 +5,0 @@ "main": "dist/index.js",

682

README.md
Isntnt is a collection of composable JavaScript runtime type predicates with TypeScript type guard declarations. Supports generics including union and intersection types.
# Generics
# Predicates
## above
`(floor: number) => (value: unknown) => value is number`
A predicate is a function that checks whether a value matches a certain type, it always returns a boolean. Well known examples of JavaScript predicates are `Array.isArray`, `isNan`, and `Number.isNaN`. With `isntnt` you add a whole slew of additional predicates to your toolbox, they are listed below.
```typescript
const isAboveZero = above(0)
```
## hasLength
## and
`<T extends Array<Predicate<any>>>(...predicates: T) => (value: unknown) => value is Predicate<Intersect<Static<T[number]>>>`
Returns `true` when you pass an object with a length property that is a valid [`length`](#isLength).
```typescript
const isBetween0And21 = and(above(0), below(21))
const isUser = shape({ name: isString })
const hasEmailAddress = at('email', isString)
const isUserWithEmail = and(isUser, hasEmailAddress) // (value: unknown) => { name: string } & { email: string }
isWithLength(value)
```
## array
`<T>(predicate: Predicate<T>) => (value: unknown) => value is Array<T>`
```typescript
const isAnyArray = array(isAny) // (value: unknown) => value is Array<any>
```
## at
`<T extends PropertyKey, U>(key: T, predicate: Predicate<U>) => (value: unknown) => value is { [P in T]: U }`
```typescript
const isAnyAtFoo = at('foo', isAny) // (value: unknown) => value is { foo: any }
```
## below
`(max: number) => (value: unknown) => value is number`
```typescript
const isBelow21 = below(21)
```
## either
`<T extends Array<Primitive>>(...literalValues: T) => (value: unknown) => value is T[number]`
```typescript
const isFooOrBar = either('foo', 'bar') // (value: unknown) => value is 'foo' | 'bar'
```
## has
`<T extends PropertyKey>(key: T) => (value: unknown) => value is { [P in T]: unknown }`
```typescript
const hasFoo = has('foo') // (value: unknown) => value is { 'foo': unknown }
```
## instance
`<T extends Constructor<any, any>>(constructor: T) => (value: unknown) => value is InstanceType<T>`
```typescript
const isInstanceofString = instance(String) // (value: unknown) => value is String
```
## literal
`<T extends Primitive>(literalValue: T) => (value: unknown) => value is T`
```typescript
const is42 = literal(42) // (value: unknown) => value is 42
```
## max
`<T extends number>(max: number) => (value: unknown) => value is number`
```typescript
const isMax255 = max(255)
```
## maybe
`<T>(predicate: Predicate<T>) => (value: unknown) => value is T | null | undefined`
```typescript
const isMaybeString = maybe(isString) // (value: unknown) => value is string | null | undefined
```
## min
`(min: number) => (value: unknown) => value is number`
```typescript
const isMin18 = min(18)
```
## noneable
Aliases [`maybe`](#maybe)
## nullable
`<T>(predicate: Predicate<T>) => (value: unknown) => value is T | null`
```typescript
const isNullableString = nullable(isString) // (value: unknown) => value is string | null
```
## object
`<T>(predicate: Predicate<T>) => (value: unknown) => value is Record<any, T>`
```typescript
const isEnum = object(isUint) // (value: unknown) => value is Record<any, number>
```
## optional
`<T>(predicate: Predicate<T>) => (value: unknown) => value is T | undefined`
```typescript
const isOptionalString = optional(isString) // (value: unknown) => value is string | undefined
```
## or
`<T extends Array<Predicate<any>>>(...predicates: T) => (value: unknown) => value is Static<T[number]>`
```typescript
const isStringOrNumber = or(isString, isNumber) // (value: unknown) => value is string | number
```
## record
`<T extends PropertyKey, U>(keyPredicate: Predicate<T>, valuePredicate: Predicate<U>) => (value: unknown) => value is Record<T, U>`
```typescript
const isDictionary = record(isString, isInt) // (value: unknown) => value is Record<string, number>
```
## shape
`<T extends Record<PropertyKey, Predicate<any>>>(predicates: T) => (value: unknown) => value is { [P in keyof T]: Static<T[P]> }`
> Note: Actual signature also considers optional members (`{ name?: T }`) in its `Predicate` type
```typescript
const isCoordinate = shape({ x: isNumber, y: isNumber }) // (value: unknown) => value is { x: number, y: number }
```
## test
`(expression: RegExp) => (value: unknown) => value is string`
```typescript
const isSlug = test(/^[\w-]+$/)
```
## tuple
`<T extends Array<any>>(...predicates: { [K in keyof T]: Predicate<T[K]> }) => (value: unknown) => value is T`
```typescript
const isPoint = tuple(isNumber, isNumber) // (value: unknown) => value is [number, number]
```
# Predicates
## isAny
`(value: unknown) => value is any`

@@ -168,4 +24,5 @@ Always returns `true`.

## isArray
`(value: unknown) => value is Array<unknown>`
Returns `true` when you pass an array.
```typescript

@@ -176,4 +33,5 @@ isArray(value)

## isArrayLike
`(value: unknown) => value is Record<number, unknown>`
Returns `true` when you pass a object that is not a function with a length property that is a valid [`length`](#isLength).
```typescript

@@ -184,4 +42,5 @@ isArrayLike(value)

## isBigInt
`(value: unknown) => value is bigint`
Returns `true` when you pass a bigint.
```typescript

@@ -192,4 +51,5 @@ isBigInt(value)

## isBoolean
`(value: unknown) => value is boolean`
Returns `true` when you pass a boolean.
```typescript

@@ -200,4 +60,5 @@ isBoolean(value)

## isDate
`(value: unknown) => value is Date`
Returns `true` when you pass a Date object.
```typescript

@@ -208,4 +69,5 @@ isDate(value)

## isDictionary
`(value: unknown) => value is Record<any, string>`
Returns `true` when you pass an object of which each property name, and each property value are a string.
```typescript

@@ -216,4 +78,5 @@ isDictionary(value)

## isFalse
`(value: unknown) => value is false`
Returns `true` when you pass `false`.
```typescript

@@ -224,4 +87,5 @@ isFalse(value)

## isFunction
`(value: unknown) => value is Function`
Returns `true` when you pass a function.
```typescript

@@ -232,4 +96,5 @@ isFunction(value)

## isInt
`(value: unknown) => value is number`
Returns `true` when you pass an integer (a whole number).
```typescript

@@ -240,4 +105,5 @@ isInt(value)

## isInt8
`(value: unknown) => value is number`
Returns `true` when you pass an [integer](#isInt) ranging from -128 to 127.
```typescript

@@ -248,4 +114,5 @@ isInt8(value)

## isInt16
`(value: unknown) => value is number`
Returns `true` when you pass an [integer](#isInt) ranging from -32,768 to 32,767.
```typescript

@@ -256,4 +123,5 @@ isInt16(value)

## isInt32
`(value: unknown) => value is number`
Returns `true` when you pass an [integer](#isInt) ranging from -2,147,483,648 to 2,147,483,647.
```typescript

@@ -264,4 +132,5 @@ isInt32(value)

## isLength
`(value: unknown) => value is number`
Alias to [`isUint32`](#isUint32).
```typescript

@@ -272,4 +141,5 @@ isLength(value)

## isMap
`(value: unknown) => value is Map<any, unknown>`
Returns `true` when you pas a Map object.
```typescript

@@ -280,4 +150,5 @@ isMap(value)

## isNegative
`(value: unknown) => value is number`
Returns `true` when you pas a negative number (including -0).
```typescript

@@ -288,5 +159,4 @@ isNegative(value)

## isNever
`(value: unknown) => value is never`
Always returns `false`;
Always returns `false`.

@@ -298,4 +168,5 @@ ```typescript

## isNone
`(value: unknown) => value is null | undefined`
Returns `true` when you pass `null` or `undefined`.
```typescript

@@ -306,4 +177,5 @@ isNone(value)

## isNull
`(value: unknown) => value is null`
Returns `true` when you pass `null`.
```typescript

@@ -314,4 +186,5 @@ isNull(value)

## isNumber
`(value: unknown) => value is number`
Returns `true` when you pass a number that is not `NaN`.
```typescript

@@ -322,4 +195,5 @@ isNumber(value)

## isObject
`(value: unknown) => value is object`
Returns `true` when you pass an object that is not `null`.
```typescript

@@ -330,4 +204,5 @@ isObject(value)

## isObjectLike
`(value: unknown) => value is ObjectLike`
Returns `true` when you pass an value that is not a boolean, `null`, or `undefined`.
```typescript

@@ -338,4 +213,5 @@ isObjectLike(value)

## isPlainObject
`(value: unknown) => value is {}`
Returns `true` when you pass an object that was constructed by `Object`.
```typescript

@@ -346,4 +222,5 @@ isPlainObject(value)

## isPositive
`(value: unknown) => value is number`
Returns `true` when you pass a positive number.
```typescript

@@ -354,4 +231,5 @@ isPositive(value)

## isPrimitive
`(value: unknown) => value is Primitive`
Returns `true` when you pass `null`, `undefined`, a boolean, bigint, number, symbol, or string.
```typescript

@@ -361,6 +239,6 @@ isPrimitive(value)

## isRegExp
`(value: unknown) => value is RegExp`
Returns `true` when you pass a RegExp object.
```typescript

@@ -371,4 +249,5 @@ isRegExp(value)

## isSerializable
`(value: unknown) => value is Serializable`
Returns `true` when you pass a [serializable primitive](#isSerializablePrimitive), a [serializable array](#isSerializableArray), or [serializable object](#isSerializableObject).
```typescript

@@ -379,4 +258,5 @@ isSerializable(value)

## isSerializableArray
`(value: unknown) => value is Array<Serializable>`
Returns `true` when you pass an array where every element is [serializable](#isSerializable).
```typescript

@@ -387,4 +267,5 @@ isSerializableArray(value)

## isSerializableNumber
`(value: unknown) => value is number`
Returns `true` when you pass a number that is not `NaN`, `Infinity`, or `-Infinity`.
```typescript

@@ -395,4 +276,5 @@ isSerializableNumber(value)

## isSerializableObject
`(value: unknown) => value is Record<string, Serializable>`
Returns `true` when you pass an object where every property is [serializable](#isSerializable).
```typescript

@@ -403,4 +285,5 @@ isSerializableObject(value)

## isSerializablePrimitive
`(value: unknown) => value is SerializablePrimitive`
Returns `true` when you pass `null`, a [serializable number](#isSerializableNumber), a boolean, bigint, symbol, or string.
```typescript

@@ -411,4 +294,5 @@ isSerializablePrimitive(value)

## isSet
`(value: unknown) => value is Set<unknown>`
Returns `true` when you pas a Set object.
```typescript

@@ -419,4 +303,5 @@ isSet(value)

## isSome
`(value: unknown) => value is Some`
Returns `true` when you pas a value other than `null` or `undefined`.
```typescript

@@ -427,4 +312,5 @@ isSome(value)

## isString
`(value: unknown) => value is string`
Returns `true` when you pas a string.
```typescript

@@ -435,4 +321,5 @@ isString(value)

## isSymbol
`(value: unknown) => value is symbol`
Returns `true` when you pas a symbol.
```typescript

@@ -443,4 +330,5 @@ isSymbol(value)

## isTrue
`(value: unknown) => value is true`
Returns `true` when you pas `true`.
```typescript

@@ -451,4 +339,5 @@ isTrue(value)

## isUint
`(value: unknown) => value is number`
Returns `true` when you pass a positive [integer](#isInteger).
```typescript

@@ -459,4 +348,5 @@ isUint(value)

## isUint8
`(value: unknown) => value is number`
Returns `true` when you pass an [unsigned integer](#isUint) ranging from 0 to 255.
```typescript

@@ -467,4 +357,5 @@ isUint8(value)

## isUint16
`(value: unknown) => value is number`
Returns `true` when you pass an [unsigned integer](#isUint) ranging from 0 to 65,535.
```typescript

@@ -475,4 +366,5 @@ isUint16(value)

## isUint32
`(value: unknown) => value is number`
Returns `true` when you pass an [unsigned integer](#isUint) ranging from 0 to 4,294,967,295.
```typescript

@@ -483,4 +375,5 @@ isUint32(value)

## isUndefined
`(value: unknown) => value is undefined`
Returns `true` when you pass `undefined`.
```typescript

@@ -491,4 +384,5 @@ isUndefined(value)

## isWeakMap
`(value: unknown) => value is WeakMap<any, unknown>`
Returns `true` when you pass a `WeakMap` object.
```typescript

@@ -498,9 +392,285 @@ isWeakMap(value)

## isWithLength
`(value: unknown) => value is { length: number }`
# Predicate factories
Predicate factories is where the real fun begins, they allow you to create and combine predicates of your own to create new predicates. By composing predicates you can describe objects, union types, number ranges, and so on.
## above
Create a predicate based on a floor value, it checks if a [number](#isNumber) exceeds the floor value it’s given. This is an analogue to the `>` operator.
```typescript
isWithLength(value)
const isAboveZero = above(0)
isAboveZero(-1) // false
isAboveZero(12) // true
```
The `isAboveZero` predicate above returns `true` when you pass a [number](#isNumber) that is greater than `0`.
## and
Create a predicate based on several other predicates, it returns `true` if every predicate that is passed also returns `true`. This is an analogue to the `&&` operator.
```typescript
const adultAge = 18
const isMinorAge = and(isUint, below(adultAge))
isMinorAge(12) // true
isMinorAge(33) // false
```
The `isMinorAge` predicate above returns `true` when you pass an [unsigned integer](#isUint) that is below 18.
```typescript
const isUser = shape({ name: isString })
const hasEmailAddress = shape({ email: isString })
const isUserWithEmail = and(isUser, hasEmailAddress)
```
The `isUserWithEmail` predicate above returns `true` when you pass an object with a `name` and an `email` property, both of which are a string.
## array
Create a predicate that checks every array element, it returns `true` when its predicate returns `true` for every element in an array.
```typescript
const isNumberArray = array(isNumber)
```
The `isNumberArray` predicate above returns `true` when you pass an array of which every element is a [number](#isNumber).
## at
Create a predicate based on a property key and another predicate, it returns `true` when its predicate returns `true` for the value of an object at its given key.
```typescript
const isStringAtName = at('name', isString)
isStringAtName({ name: 'Jane' }) // true
isStringAtName({ name: null }) // false
```
The `isStringAtName` predicate above returns `true` when you pass an object of which the `name` property is a string.
## below
Create a predicate based on a ceiling value, it checks if a [number](#isNumber) is below the ceiling value it’s given. This is an analogue to the `<` operator.
```typescript
const isBelow100 = below(100)
isBelow100(124) // false
isBelow100(32) // true
```
The `isBelow100` predicate above returns `true` when you pass a [number](#isNumber) that is less than `100`.
## either
Create a predicate based on several [literal](#literal) values, it returns `true` if a value matches either of the primitive values it’s given.
```typescript
const isAOrB = either('a', 'b')
isAOrB('a') // true
isAOrB('c') // false
```
The `isAOrB` predicate above returns `true` when you pass either `a`, or `b`.
## has
Create a predicate based on a property key, it returns `true` if an object has a property of the key it’s given.
```typescript
const hasName = has('name')
hasName({ name: null }) // true
hasName({ age: 36 }) // false
```
The `hasName` predicate above returns `true` when you pass an object that has a `name` property.
## instance
Create a predicate based on a constructor, it returns `true` if an object is an instance of the constructor key it’s given.
```typescript
const isInstanceofString = instance(String)
isInstanceofString(new String('foo')) // true
isInstanceofString('foo') // false
```
The `isInstanceofString` predicate above returns `true` when you pass a String object.
## literal
Create a predicate based a [primitive](#isPrimitive) value, it returns `true` if a value equals the primitive value it’s given.
```typescript
const is42 = literal(42)
is42(42) // true
is42(43) // false
```
The `is42` predicate above returns `true` when you pass `42`.
## max
Create a predicate based on a max. value, it checks if a [number](#isNumber) is below or equal to the max. value it’s given. This is an analogue to the `<=` operator.
```typescript
const isMax100 = max(100)
isMax100(100) // true
isMax100(101) // false
```
The `isMax100` predicate above returns `true` when you pass a [number](#isNumber) that is below or equal to `100`.
## maybe
Create a predicate based on another predicate, it checks if a value matches it’s given predicate, or equals `null` or `undefined`.
```typescript
const isMaybeString = maybe(isString)
isMaybeString(null) // true
isMaybeString(12) // false
```
The `isMaybeString` predicate above returns `true` when you pass a string, `null`, or `undefined`.
## min
Create a predicate based on a min. value, it checks if a [number](#isNumber) is above or equal to the min. value it’s given. This is an analogue to the `>=` operator.
```typescript
const isMin100 = min(100)
isMin100(100) // true
isMin100(99) // false
```
The `isMin0` predicate above returns `true` when you pass a [number](#isNumber) that is above or equal to `100`.
## noneable
Aliases [`maybe`](#maybe).
## nullable
Create a predicate based on another predicate, it checks if a value matches it’s given predicate, or equals `null`.
```typescript
const isNullableString = nullable(isString)
isNullableString(null) // true
isNullableString(12) // false
```
The `isNullableString` predicate above returns `true` when you pass a string or `null`.
## object
Create a predicate that checks every object property, it returns `true` when its predicate returns `true` for every object value.
```typescript
const isEnumerable = object(isUint)
```
The `isEnumerable` predicate above returns `true` when you pass an object of which every element is an [unsigned integer](#isUint).
## optional
`<T>(predicate: Predicate<T>) => (value: unknown) => value is T | undefined`
```typescript
const isOptionalString = optional(isString)
isOptionalString(undefined) // true
isOptionalString(12) // false
```
The `isOptionalString` predicate above returns `true` when you pass a string or `undefined`.
## or
Create a predicate based on several other predicates, it returns `true` if some predicate that is passed also returns `true`. This is an analogue to the `||` operator.
```typescript
const isContent = or(isString, isSerializableNumber)
isContent(12) // true
isContent(null) // false
```
The `isContent` predicate above returns `true` when you pass a string or a [primitive number](#isPrimitiveNumber).
```typescript
const isStringOrNumber = or(isString, isNumber)
isStringOrNumber(8) // true
isStringOrNumber([]) // false
```
## record
Create a predicate based on a key predicate and a value predicate, it returns `true` if each property key of an object returns `true` for its key predicate, and each value returns `true` for its value predicate.
```typescript
const isValidKey = either('a', 'b')
const isKeyValueMap = record(isValidKey, isInt)
isKeyValueMap({ a: 2 }) // true
isKeyValueMap({ a: null }) // false
isKeyValueMap({ c: 2 }) // false
```
The `isKeyValueMap` predicate above returns `true` when you pass an object where each key is either `a` or `b`, and each property value is an [integer](#isInt).
## shape
Create a predicate based on a predicate object, it returns `true` if each property value of an object returns `true` for its corresponding predicate.
```typescript
const isPoint = shape({ x: isNumber, y: isNumber })
isPoint({ x: 12, y: 36 }) // true
isPoint({ x: 12 }) // false
```
The `isPoint` predicate above returns `true` when you an pass an object where both `x` and `y` properties are a [number](#isNumber).
## test
```typescript
const isSlug = test(/^[A-Z0-9-]+$/i)
isSlug('foo-bar') // true
isSlug('!#$') // false
```
The `isSlug` predicate above returns `true` when you an pass a string that matches `/^[A-Z0-9-]+$/i`.
## tuple
Create a predicate based on index-based predicates, it returns `true` if the element at each index of an array with a fixed length returns `true` for its corresponding predicate.
```typescript
const isLatitude = and(min(-90), max(90))
const isLongitude = and(min(-180), max(180))
const isLatLong = tuple(isLatitude, isLongitude)
isLatLong(45, -120) // true
isLatLong(120, 200) // false
```
The `isLatLong` predicate above returns `true` when you an pass an array with a length of 2 where index 0 is a latitude, and index 1 is a longitude value.
# Types

@@ -511,13 +681,27 @@

```typescript
Intersect<A | B> // A & B
type User = Intersect<{ name: string } | { email: string }>
```
equals
```typescript
type User = {
name: string
} & {
email: string
}
```
## Maybe
Unions a type with `null` and `undefined`.
```typescript
Maybe<T> // T | null | undefined
type MaybeString = Maybe<string>
```
equals
```typescript
type MaybeString = Maybe<string> // string | null | undefined
type MaybeString = string | null | undefined
```

@@ -527,14 +711,26 @@

Union of `null` and `undefined`.
```typescript
None // null | undefined
type NoneType = None
```
equals
```typescript
type NoneType = null | undefined
```
## Nullable
Unions a type with `null`.
```typescript
Nullable<T> // T | null
type NullableString = Nullable<string>
```
equals
```typescript
type NullableString = Nullable<string> // string | null
type NullableString = string | null
```

@@ -544,8 +740,12 @@

Unions a type with `undefined`.
```typescript
Optional<T> // T | undefined
type OptionalString = Optional<string>
```
equals
```typescript
type OptionalString = Optional<string> // string | undefined
type OptionalString = string | undefined
```

@@ -555,50 +755,90 @@

Describes a predicate function signature
```typescript
Predicate<T> // (value: unknown, ...rest: Array<unknown>) => value is T
type IsString = Predicate<string>
```
equals
```typescript
type IsString = <T>(value: T) => value is Extract<T, string>
```
## Primitive
Union of all primitive types.
```typescript
Primitive // null | undefined | boolean | number | string | symbol | bigint
type PrimitiveType = Primitive
```
equals
```typescript
type PrimitiveType = null | undefined | boolean | number | string | symbol | bigint
```
## Serializable
```typescript
Serializable // SerializableArray | SerializableObject | SerializablePrimitive
type SerializableType = Serializable
```
equals
```typescript
type SerializableType = SerializableArray | SerializableObject | SerializableObject
```
## SerializableArray
```typescript
SerializableArray // Array<Serializable>
type SerializableArrayType = SerializableArray
```
equals
```typescript
type SerializableArrayType = Array<Serializable> | ReadonlyArray<Serializable>
```
## SerializableObject
```typescript
SerializableObject // Partial<{ [key: string]: Serializable }>
type SerializableObjectType = SerializableObject
```
equals
```typescript
type SerializableObjectType = { [key: string]: Serializable | undefined }
```
## SerializablePrimitive
```typescript
SerializablePrimitive // null | boolean | number | string
type SerializablePrimitiveType = SerializablePrimitive
```
equals
```typescript
type SerializablePrimitiveType = null | boolean | number | string
```
## Some
Excludes `null` and `undefined` from type.
```typescript
Some // Function | boolean | bigint | number | string | symbol | object
Some<T> // Exclude<T, undefined | null>
type SomeType = Some
type SomeString = Some<string | null>
```
equals
```typescript
// Make sure `T` is not `null` or `undefined`
type Option<T extends Some, E extends Error> = T | E
// Remove `null` or `undefined` from a type
type MaybeString = Optional<string> // string | null | undefined
type SomeString = Some<MaybeString> // string
type SomeType = Function | boolean | bigint | number | string | symbol | object
type SomeString = string
```

@@ -608,8 +848,12 @@

Extracts type parameter from Predicate type. This is useful to extract TypeScript types from (complex) predicates.
```typescript
Static<Predicate<T>> // T
type PredicateType = Static<Predicate<string>>>
```
equals
```typescript
type True = Static<typeof isTrue> // true
type PredicateType = string
```

3

src/lib/predicates.ts

@@ -0,1 +1,2 @@

export { hasLength } from './predicates/hasLength'
export { isAny } from './predicates/isAny'

@@ -43,2 +44,2 @@ export { isArray } from './predicates/isArray'

export { isWeakMap } from './predicates/isWeakMap'
export { hasLength as isWithLength } from './predicates/isWithLength'
export { isWithLength } from './predicates/isWithLength'

5

src/lib/predicates/isArrayLike.ts
import { and } from '../generics/and'
import { at } from '../generics/at'
import { isFunction } from './isFunction'
import { isLength } from './isLength'
import { ArrayLike, Predicate } from '../types'
import { hasLength } from './hasLength'
export const isArrayLike = and(
at('length', isLength),
hasLength,
(value: unknown): value is any => !isFunction(value),
) as Predicate<ArrayLike>

3

src/lib/predicates/isWithLength.ts
import { at } from '../generics/at'
import { isLength } from './isLength'
export const hasLength = at('length', isLength)
/** @deprecated */
export const isWithLength = at('length', isLength)

17

src/lib/types.ts

@@ -1,14 +0,1 @@

export type InferredPartial<T extends {}> = {
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? K : never
}[keyof T]]: InferredPartial<T[P]>
} &
Partial<
{
[P in {
[K in keyof T]: Extract<T[K], undefined> extends never ? never : K
}[keyof T]]: InferredPartial<T[P]>
}
>
export type Predicate<T> = <U>(value: U) => value is Extract<U, T>

@@ -42,5 +29,3 @@

export type ObjectLike = {
[P in PropertyKey]: unknown
}
export type ObjectLike = Exclude<Some, boolean>

@@ -47,0 +32,0 @@ export type Primitive = SerializablePrimitive | undefined | symbol | bigint

dist/esm/lib/predicates.js.map

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dist/esm/lib/predicates/isArrayLike.js.map

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dist/esm/lib/predicates/isWithLength.js.map

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dist/lib/predicates.js.map

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dist/lib/predicates/isArrayLike.js.map

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dist/lib/predicates/isWithLength.js.map

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