Typed

Some Extra Guards and Types for TypeScript

Gist, Vibes, Philosophy, Misc.

• Lightweight / Minimal / KISS
• Simplify basic type checking during runtime with guards.
• Add a few types and utility classes that make generic typing a bit easier.
• No nulls, ever, just undefined.
  • Nothing against null, it just causes a lot of problems to have both null and undefined.
  • Most guards in this package will throw an error if a null is encountered.
  • undefineds are OK!
• favor shorter variable names when the abbreviations/shorthand names are widely recognized (i.e. isStr over isString).
  • favor more verbose names when no widely recognized alternative exists
  • isObjWithOptionalProp

Examples

TODO: more examples

import { isDef } from "typed/guards";

function someUselessFunc(idk?:string|object = undefined):string|object|undefined {
    return idk;
}

let anUndefinedVar = someUselessFunc(undefined);
if (!isDef(anUndefinedVar)) {
    console.log("anUndefinedVar is undefined");
}

let aNullVar = someUselessFunc(null);
!isDef(anUndefinedVar); // throws an error because we don't like null's here

let aString = someUselessFunc("a real string");
if (!isDef(aString))
{
    throw new Error("its not defined.")
}

let anObjectOrString = aString; // the compiler now knows that anObjectOrString is of type object or string because we used the isDef guard.

let definitelyAString = isStr()

Package Reference

TODO!