Thanks to this post from Toby Farley (Shadow Chicken), I had an inspiration to build my own tiny little nano "typescript" running without compilation.
Ok, typescript provides much more, but if you only need some typechecks, this little routine would do the trick:
/* ==================================================
Nano typeCheck
Valid types
"var": Variant - all types allowed
"string"
"number"
"bigInt"
"boolean"
"object"
"array"
"date"
"set"
"function"
================================================== */
function typeCheck(v) {
if ((typeof v) !== "object") throw (`Parameter must be Object in function ${typeCheck.caller.name}`)
// Build return value array
let res = Object.entries(v).map((a, i) => {
let [typ, val] = a; // get key/values
typ = typ.charAt(0).toUpperCase() + typ.slice(1) // Capitalize
if (typ === "Var") // Variant type
return val
if (val.constructor.name !== typ) // check type
throw (`Type error parameter ${i + 1} is not ${typ} in function ${typeCheck.caller.name}`)
return (val)
})
return res
}
function myFunc(a,b,c,d) {
typeCheck({ string: a, boolean: b, array: c, var: d })
console.log(a)
console.log(b)
console.log(c)
console.log(d)
}
myFunc( "5", true, [1, 2, 3, 4, 5], "Do what you want")
You can also submit typ declaration with the parameters like this:
function myFunc(pars) {
let [a, b, c, d] = typeCheck(pars)
console.log(a)
console.log(b)
console.log(c)
console.log(d)
}
myFunc({ string: "5", boolean: true, array: [1, 2, 3, 4, 5], var: "Do what you want" })
Types can be named using the standard type names with lower or upper case, so both would be accepted:
{ string: a, boolean: b, array: c, var: d }
{ String: a, Boolean: b, Array: c, Var: d }
Tell me, what you think.
P.S.: This post was changed after the first sumbission to show different ways of usage.
Top comments (5)
wow !!
this is awesome !!
I think it's already very great
you can add more unique features
it can be next big thing
nice
The main benefit of Typescript is that it catches type unsoundness in development without the need to add code to the production bundle.
Checking types in production is the field of scheme libraries. While your solution is interesting as an example, it cannot compete with scheme libraries like valibot or zod.
Be serious: does it look like the next big thing? It's just an example, but I like the sceme....
No, not really. I just wanted to point out that this is something different than TypeScript and that others have found a niche for similar solutions that even work very well together with TypeScript.
Nice, but I agree with Alex, at runtime, zod is a must