Native TypeScript containers for generic value storage. Reliably store and retrieve typed values without writing validation or type checking code. Use built-in types or define your own.
What does it do?
import {StrongInt, makeInt} from '@toreda/strong-types'; // int with initial value 10. const int = makeInt(10, 0); // Prints 10. It always return an int. console.log(int()); // Set the value int(11); // Prints 11. console.log(int()); // Won't set the value - it's not an int. int(null); int(undefined); int(3.33); int({}); // Prints 11 console.log(int());Each built-in type exports a type and make function. The below examples use StrongInt but work the same using: StrongArray, StrongBoolean, StrongDouble, StrongInt, StrongString, and StrongUInt.
import {StrongInt, makeInt} from '@toreda/strong-types'; const initial = 11; const fallback = 55; const int = makeInt(initial, fallback); // Returns 11 - initial value was 11. const value = int();import {StrongInt, makeInt} from '@toreda/strong-types'; const fallback = 919; const int = makeInt(null, fallback); // value is 919 - initial value was null, so fallback was // returned instead to maintain the function's return type guarantee. const value = int();get(fallback: T): TCallcontainer.get(fallback)when a per-call fallback is preferred instead of the container's default fallback.
import {StrongInt, makeInt} from '@toreda/strong-types'; const int = makeInt(null, 555); const fallback = 331; // Prints 331 (fallback) instead of 555 (container default fallback). console.log(value.get(fallback));getNull(): T | nullCallcontainer.getNull()to the current value, even if null. Value will never be undefined and will always return either null, or a value of container's generic type T.
NOTE: getNull DOES NOT take a fallback argument and will not return the container's default fallback. It always returns value (null or StrongType<T>).
import {StrongInt, makeInt} from '@toreda/strong-types'; const fallback = 919; const int = makeInt(null, fallback); // Prints null. Default fallback is not used for `getNull` calls. console.log(int.getNull());import {StrongInt, makeInt} from '@toreda/strong-types'; const initial = 331; const fallback = 400; const int = makeInt(initial, fallback); // value is 331 - the int's initial value. const value = int(); // Set int to a new value. int(555); // value is 555 - the value we updated int to. const value = int(); import {StrongInt, makeInt} from '@toreda/strong-types'; const initial = 414; const fallback = 500; const int = makeInt(initial, fallback); // value is 414 - the int's initial value. const value = int(); // Set value to null. int(null); // value is 500 - Fallback returned because value was null. const value = int();Call myContainer.reset() to reset value without creating a new StrongType container. Default Fallback will not be reset. Useful for unit testing and serverless environments where the previous container value or state is unknown.
import {StrongInt, makeInt} from '@toreda/strong-types'; const initial = 515; const fallback = 600; const int = makeInt(initial, fallback); // value is 515 (the initial value). const value = int(); // Reset container value int.reset(); // Prints 600 (fallback). value was reset to null, // fallback was returned to maintain return type guarantee. console.log(int());StrongType containers validate value inputs before setting. Bad values are ignored and will not cause a throw. Each built-in container type provides specific guarantees for which values are allowed.
import {StrongInt, makeInt} from '@toreda/strong-types'; const int = makeInt(50, 100); // success is false. // container.value is still it's initial value 50 because 1.5 is not an int. // StrongInt does not round or truncate non-integers. They are simply ignored. const success = int(1.5);StrongArray, arraysStrongBoolean, booleans (strict)StrongDouble, doublesStrongInt, integersStrongUInt, unsigned integersStrongString- strings
Creating and using a StrongMap class.
import {StrongMap, StrongInt, StrongString, makeInt, makeString} from '@toreda/strong-types'; export class SomeConfig extends StrongMap { public readonly counter: StrongInt; public readonly name: StrongString; constructor(json: any) { super(); this.counter = makeInt(0, 0); this.name = makeString(null, 'TreeBeard'); this.parse(json); } } // Use it const myConfig = new SomeConfig(); // Prints '0' console.log(myConfig.counter()); // Prints 'Treebeard' console.log(myConfig.name());Creating a StrongMap and loading values from JSON
import {StrongMap, StringInt, StrongString, makeInt, makeString} from '@toreda/strong-types'; export class SomeConfig extends StrongMap { public readonly counter: StrongInt; public readonly name: StrongString; constructor(json?: any) { super(); this.counter = makeInt(0, 0); this.name = makeString(null, 'TreeBeard'); this.parse(json); } } const myJSON = { 'counter': 99, 'name': 'Sauron' }; // Load the recursively parse a JSON object. const myConfig = new SomeConfig(myJSON); // Prints 99 - myJSON.counter was loaded into SomeConfig.counter at instantiation. console.log(myConfig.counter()); // Prints 'Sauron' - myJSON.name was loaded into SomeConfig.name at instantiation. console.log(myConfig.name());Converting a StrongMap to a json object
import {StrongMap, StringInt, StrongString, makeInt, makeString} from '@toreda/strong-types'; export class SomeConfig extends StrongMap { public readonly counter: StrongInt; public readonly name: StrongString; constructor(json?: any) { super(); this.counter = makeInt(0, 0); this.name = makeString(null, 'TreeBeard'); this.parse(json); } } const myJSON = { 'counter': 99, 'name': 'Sauron' }; // Create the StrongMap with myJSON data const myConfig = new SomeConfig(myJSON); // Change a value in the StrongMap myConfig.name('Gandalf'); // {counter: 99, name: 'Gandalf'} const configAsJSON = myConfig.jsonify();import {StrongArray, makeArray} from '@toreda/strong-types';- Arrays holding any type (e.g.
T[]) - Accepts empty arrays (e.g.
[])
import {StrongBoolean, makeBoolean} from '@toreda/strong-types';- Strict booleans:
trueorfalseonly. - No type coercion (e.g.
1or0will be rejected).
import {StrongDouble, makeDouble} from '@toreda/strong-types';numbervalues between and including Number.MIN_VALUE and Number.MAX_VALUE.- Rejects
NaNvalues.
import {StrongInt, makeInt} from '@toreda/strong-types';numbervalues between and including Number.MIN_VALUE and Number.MAX_VALUE.NaNvalues are rejected.
import {StrongString, makeString} from '@toreda/strong-types';stringvalues of any valid length.
import {StrongUInt, makeUInt} from '@toreda/strong-types';- Integers between and including 0 and
Number.MAX_SAFE_INTEGER. - Rejects numbers which are non-integers (e.g.
1.5) - Rejects
NaN - Rejected negative integers (e.g.
-22).
Each built-in type like StrongInt and StrongUInt are helper functions wrapping StrongType<T>. They also apply validators which guarantee the StrongType<T> value behaves as expected. While built-ins are provided for convenience, you can create custom types with your own validators.
import {StrongType, makeStrong} from '@toreda/strong-types'; export type MyOwnType = { id: string | null; name: string | null; }; const initial: MyOwnType = { id: 'hello', name: 'my name is' }; const fallback: MyOwnType = { id: null, name: null }; const myObj = makeStrong<MyOwnType>(initial, fallback);Install @toreda/strong-types directly from NPM or clone the Github repo.
- Open a shell (or console).
- Navigate to the the StrongTypes root project folder.
- Enter the following commands in order. Wait for each to complete before typing the next.
yarn- Open a shell (or console).
- Navigate to the the StrongTypes root project folder.
- Enter the following commands in order. Wait for each to complete before typing the next.
npm installInstall or clone StrongTypes (see above).
StrongTypes tests are written with Jest which is also a project dev dependency.
Installing jest is not required after project dependencies are installed (see above).
yarn testThe next steps are the same whether you installed the package using NPM or cloned the repo from Github.
Enter the following commands in order from the StrongTypes root project folder.
yarn buildEnter the following commands in order from the StrongTypes root project folder.
npm run-script buildMIT © Toreda, Inc.