kofno

map<B>(f: (a: A) => B): Decoder<B>;

kofno

/**
 * Applies the `decoder` to all of the elements of an array.
 */
export declare const array: <A>(decoder: Decoder<A>) => Decoder<A[]>;
/**
 * Decodes the value at a particular field in a JavaScript object.
 */
export declare const field: <A>(name: string, decoder: Decoder<A>) => Decoder<A>;

kofno

import { oneOf, string, number } from 'jsonous';

const numberToString = number().map(n => n.toString());
const decoder = oneOf([string(), numberToString]);

decoder.decodeAny('forty-two');
// --> Ok('forty-two');

decoder.decodeAny(42);
// --> Ok('42');

kofno

import { maybe, string, field } from 'jsonous';
        
const decoder = field('foo', maybe(string()));

decoder.decodeAny({ foo: 'bar' }) 
// --> Ok(Just('bar'))

decoder.decodeAny({ foo: null })  
// --> Ok(Nothing)

kofno

import { at, number } from 'jsonous';

at(['foo', 0, 'bar'], number()).decodeAny({ foo: [{ bar: 42 }] })
// --> Ok(42)

at(['foo', 1, 'bar'], number()).decodeAny({ foo: [{ bar: 42 }] })
// --> Err('Path failure: Expected to find path '["foo",1]' in {"foo":[{"bar":42}]}')

kofno

import { field, string, boolean, number, succeed } from 'jsonous';

const decoder = 
  field('foo', string()).map(s => s + '-ish').andThen(foo =>
  field('bar', number()).map(n => n*2).andThen(bar =>
  field('baz', boolean()).map(b => !b).andThen(baz =>
  succeed({ foo, bar, baz }))));

decoder.decodeAny({ foo: 'hello', bar: 42, baz: true }); 
// --> Ok({ foo: 'hello-ish', bar: 84, baz: false })

kofno

import { string } from 'jsonous';

const decoder = string().map(s => s + '-ish');

decoder.decodeAny('soon'); // --> Ok('soon-ish')

kofno

import { string, field } from 'jsonous';

const decoder = field('foo', string());

decoder.decodeAny({ foo: 'bar' }); // --> Ok('bar')
decoder.decodeAny({ baz: 'bar' }); // --> Err('Expected to find an object with key 'foo'. Instead found { baz: 'bar' }')
decoder.decodeAny({ foo: 8 });     // --> Err('Error found in field 'foo' of { foo: 8 }: Expected a string. Instead found 8.')

kofno

import { array, string } from 'jsonous';

const decoder = array(string());

decoder.decodeAny([ 'foo', 'bar' ]);    // --> Ok(['foo', 'bar'])
decoder.decodeAny('foo');               // --> Err('Expected an array. Instead found foo')
decoder.decodeAny([ 'foo', 42, 'bar']); // --> Err('Error found in array at [1]: Expected a string. Instead found 42')

kofno

import { string } from 'jsonous';

const decoder = string();

decoder.decodeAny("foo"); // --> Ok("foo")
decoder.decodeAnt(8);     // --> Err("Expected to find a string. Instead found 8")