@type-map-for/core

Core type utilities for the @type-map-for library ecosystem.

Installation

npm install @type-map-for/core

Types

FieldTypeFor<T>

Maps TypeScript primitives to canonical field type strings:

import type { FieldTypeFor } from '@type-map-for/core';

type Examples = {
  str: FieldTypeFor<string>;        // 'string'
  num: FieldTypeFor<number>;        // 'int32' | 'float'
  bool: FieldTypeFor<boolean>;      // 'bool'
  arr: FieldTypeFor<string[]>;      // 'string[]'
  obj: FieldTypeFor<{ x: number }>; // 'object'
};

MapType<FT, M>

Translates field types via lookup map:

import type { MapType } from '@type-map-for/core';

type SqlMap = { string: 'text'; 'string[]': 'text[]'; bool: 'boolean' };
type SqlString = MapType<'string', SqlMap>;     // 'text'
type SqlArray = MapType<'string[]', SqlMap>;    // 'text[]'
type SqlBool = MapType<'bool', SqlMap>;         // 'boolean'

Utility Types

import type { IsArray, IsOptional, ItemType, RequiredKeys } from '@type-map-for/core';

type User = { name: string; email?: string; tags: string[] };

type NameIsArray = IsArray<User['name']>;        // false
type TagsIsArray = IsArray<User['tags']>;        // true
type EmailOptional = IsOptional<User['email']>;  // true
type NameOptional = IsOptional<User['name']>;    // false
type TagsItem = ItemType<User['tags']>;          // string
type Required = RequiredKeys<User>;              // 'name' | 'tags'

Contributing

Issues and pull requests welcome at github.com/nathancanine/type-map-for.

License

MIT