$mol_schema

Runtime typing schemas

Schema API

• .toString() - identity of schema.
• .check(val) - type guard.
• .guard(val) - strict parser.
• .cast(val) - relaxed caster.
• .default - default value for casting.

Leaf schemas

• $mol_schema_enum(...options) - some of constant values (first value as default).
• $mol_schema_boolean - true or false (default).
• $mol_schema_string - any string ("" as default).
  • $mol_schema_pattern(regexp) - string that matched to regexp ("" as default).
• $mol_schema_float - any number (NaN as default).
• $mol_schema_integer - integer number (0 as default).
• $mol_schema_range(min,max) - range of values between min (default) and max.
  • $mol_schema_positive - value >= 0
    • $mol_schema_natural - natural number from 0 (default).
  • $mol_schema_negative - value <= 0

Composition schemas

• $mol_schema_some(...variants) - some of schemas (default of first as default).
  • $mol_schema_maybe(schema) - value or null or undefined (undefined as default).
• $mol_schema_every(...schemas) - every of schemas for same value (first default casted through all of them).
• $mol_schema_list(item) - array of same types schema ([] as default).
• $mol_schema_dict(key,val) - key-value dictionary schema ({} as default).
• $mol_schema_record({...fields}) - object with typed fields (object with default fields values by default).

Complex example

export abstract class $my_user_main extends $mol_schema_dict({
	name: $mol_schema_string,
	age: $mol_schema_natural,
}) {}

export abstract class $my_user_full extends $mol_schema_dict({
	... $my_user_full.Fields,
	bio: $mol_schema_string,
	flags: $mol_schema_dict( $mol_schema_string, $mol_schema_boolean ),
}) {}

export abstract class $my_article_full extends $mol_schema_partial({
	title: $mol_schema_string,
	body: $mol_schema_string,
	author: $my_user_full,
}) {}

export abstract class $my_article_search extends $mol_schema_some([
	$mol_schema_dict({
		data: $mol_schema_list( $my_article_full ),
	}),
	$mol_schema_dict({
		fail: $mol_schema_pattern( /^\w+$/ ),
	}),
]) {}

response = $my_article_search.guard( response ) // Exception on wrong data

response = $my_article_search.cast( response ) // Defaults instead wrong data

if( $my_user_main.check( user ) ) {
	// user is $my_user_main now
}

const article = $my_article_full.default // default article state

Usage from NPM

import {
	$mol_schema_record: Rec,
	$mol_schema_string: Str,
	/// ...
} from 'mol_schema'

export class Article extends Rec({
	title: Str,
	body: Str,
}) {}