daolou / etype

Extra types for TypeScript

etype

Extra types for TypeScript.

Most of the time we can be sure that the type of a variable is int. However, there is no int type in TypeScript, so we have to write code with comment like this:

/** age is int */
const age: number;

Is there a better way? Of course! We can define a type alias like this:

type int = number;

const age: int;

In this way, although we can not limit the type of value of age, it makes the code more readable.

Based on this idea, we provides some extra types for TypeScript.

Usage

Install:

npm install etype --save-dev

Import in your ts files:

import type { int } from 'etype';

const age: int;

Import in Deno:

import type { int } from 'https://deno.land/x/etype/mod.ts';

const age: int;

Types

Type	Description	Example	Real Type
int	32-bit signed two's complement integer, which has a minimum value of -2^31 and a maximum value of 2^31-1	0, 1, 2, -1, -2147483648, 2147483647	number
float	Single-precision 32-bit IEEE 754 floating point	0.1, -1.23	number
IntString	Int-like-string	"100", "-1"	string
FloatString	Float-like-string	"1.00", "-0.1"	string
DateString	Date-like-string which can be converted to Date object by new Date(foo)	"Mon, 19 Oct 2020 13:09:21 GMT", "2020-09-10 17:28:35"	string
JSONString	JSON-string which can be converted to json object by JSON.parse(foo)	"{\"hello\":\"world\"}"	string
BooleanInt	Use int to represent a boolean	0, 1	0 | 1
AnyFunction	Represent to any function	/	(...args: any[]) => any
AnyObject	Represent to any object	/	Record<string | number | symbol, any>
OmitValueType	Select the value type from T to be an attribute of V, and combine these attributes	interface A {a: string; b: boolean; c: number; d: number}, OmitValueType<A, number> => {a: string; b: boolean;}	/
PickValue	Select the value type from T to be an attribute of V, and combine these attributes	interface A {a: string; b: boolean; c: number; d: number},PickValue<A, number> => 'c'|'d'	/
PartialKey	Remove some properties from T	interface A {a: string; b: boolean; c: 'f'|'m';},PartialKey<A, 'a'|'b'> => {c: 'f'|'m';}	/

Suggestions and pull requests are welcome.

Reference

• Java Primitive Data Types
• Type Aliases
• Please provide a json basic type