@easrng/schema

Create efficient runtime validators from your TypeScript types, right in your editor, with idiomatic isolatedDeclarations support.

Installation

``bash
pnpm install @easrng/schema


or

npm install @easrng/schema

or

yarn add @easrng/schema
`

Usage

Write your TypeScript type:

`ts
interface MySchema {
hello: "world";
}
`

Declare a schema, then autocomplete the string:

`ts
import { schema, type Schema } from "@easrng/schema";

interface MySchema {
hello: "world";
}
const mySchema: Schema = schema("│");
// ╭^──────────────────┄┄
// │ '{"type":"object"…
// ╰─────────────────┄┄┄
`

Use your new schema:

`ts
import { schema, type Schema } from "@easrng/schema";

interface MySchema {
hello: "world";
}
const mySchema: Schema = schema(
'{"type":"object","properties":{"hello":{"const":"world"}},"required":["hello"]}',
);
const result = mySchema.validate(0);
if (result.issues) {
console.error(result.issues);
} else {
console.log(result.value);
}
`

Standard Schema utilities

This package also provides helper functions for any Standard Schema:

`ts
import { is } from "@easrng/schema/util";
const s = "some string" as unknown;
if (is(stringSchema, s)) {
console.log("works with TypeScript");
void s;
// ^? const s: string
}
`

`ts
import { assert } from "@easrng/schema/pretty";
import { schema, type Schema } from "@easrng/schema";

const mySchema: Schema<{ prop: number }> = schema(
'{"type":"object","properties":{"prop":{"type":"number"}},"required":["prop"]}',
);
assert(mySchema, {
prop: "invalid value",
});

/**
* Prints:
*
* × Schema validation failed:
* ╭──┄┄
* │ {
* │ prop: 'invalid value'
* ┊ ╶───────┬───────╴
* ┊ ╰─ expected number
* │ }
* ╰──┄┄
*
*/
``