nicescript

NiceScript

A naive attempt to simplify life of a fellow JavaScript programmer. NiceScript.org Twitter

Example ( JS Bin )

const { Box, Div, B, Switch } = nice;

const tasks = Box(['Feed the fish', 'Buy milk']);

const decorate = Switch
  .equal('Watch tv')('Read book')
  .match(/buy/i).use(s => [s, B(' $').color('#3A3')]);

const taskView = t => Div(t)
  .margin('1em 0')
  .padding('.5em')
  .borderRadius('.5em')
  .backgroundColor('#DEF');

Box.by(tasks, ts => Div(ts.map(decorate).map(taskView))).show();

tasks.push('Walk the dog', 'Watch tv');

More examples:

• Ball game ( JS Bin )
• Todo list ( JS Bin )
• Tic Tac Toe ( JS Bin ) ( Tutorial )

Install

npm install nicescript

Then in node.js script:

const nice = require('nicescript')();

Browser:

<script src="https://unpkg.com/nicescript/nice.js"></script>

or

<script src="https://cdn.jsdelivr.net/npm/nicescript/nice.js"></script>

Tests

npm test

Basic features

• Types
• Functions - adds couple features to regular JS functions.
• Switch - finally convenient.
• Boxes - to handle state changes.
• Html - use all above to to create html UI.

Nice values

Single values

const n = nice(5);

//read value
n();      // 5

//write value
n(6);     // n
n();      // 6

Object values

const o = nice.Object({ a: 1 });

//get value
o('a');         // 1
o('b');         // nice.NOT_FOUND

//set value
o('b', 5);      // o
o('b');         // 5

Types

Each value in NiceScript has a type. Here is a root of types hierarchy:

• Anything
  • Something
    • Value
      • Object
        • Array
        • Html
      • Single
        • String
        • Number
        • Boolean
    • Function
    • Box
    • Ok
  • Nothing
    • Error
    • Undefined
    • Null
    • NotFound
    • Fail
    • ...

Wrapping values

Call nice with js value to wrap it with most appropriate type.

const nice = require('nicescript')();
nice(4);        // nice.Number;
nice("");       // nice.String;
nice(true);     // nice.Boolean;
nice({});       // nice.Object;
nice([]);       // nice.Array;
nice(1, 2, 3);  // nice.Array;
nice(null);     // nice.Null;

User types

nice.Type('Dog')
  .String('title')
  .Number('weight')
  .by((z, title) => z.title(title));

let d = nice.Dog('Jim').weight(5);
d.name();       // Jim 
d.weight();     // 5

// by default created type extends nice.Object
d.is.Object()   // true

Type name should start with capital letter.

Functions

// Creating anonymous function
const f = nice.Function(n => n + 1);
f(1);               // 2

// Named functions will be added to nice
const plusTwo = nice.Function('plusTwo', n => n + 2);
//or nice.Function(function plusTwo(n) { return n + 2; });
plusTwo(1);         // 3
nice.plusTwo(1);    // 3

// Check argument type
const x2 = nice.Function.number('x2', n => n * 2);
x2(21);             // 42
nice.x2(21);        // 42
nice.Number(1).x2();// 42
x2('q');            // throws "Function  can't handle (String)"

// now let's overload x2 for strings
x2.string(s => s + '!');
x2(21);             // 42
x2('q');            // q!

Function name should start with lowercase letter.

Function types

Mapping

Clean function that do not changes it's arguments. NiceScript will always wrap result of Mapping.

nice.Mapping.Number.Number('times', (a, b) => a * b);
const n = nice(5);
const n2 = n.times(3).times(2); // nice.Number(30)
n()                             // 5
n2()                            // 30;

Check

Returns boolean. Never changes it's arguments. After definition named Check can be used in Switch and 'is' statements.

Action

Changes first argument. Action always returns it's first argument so you can call multiple actions in a row.

nice.Action.Number.Number('times', (a, b) => a * b);
const n = nice(5);
n.times(3).times(2);            // n
n();                            // 30;

Switch

Delayed argumet

const f = nice.Switch
  .equal(1)(11)
  .number(22)
  .string.use(s => s + '!')
  .Nothing(':(')
  .default(42);
f(1);           // 11
f(3);           // 22
f('qwe');       // "qwe!"
f([]);          // 42
f(0);           // 42
f(undefined);   // :(
f(null);        // :(

Instant argument

nice.Check('meat', v => ['pork', 'beef'].includes(v));
const tiger = { say: console.log };
function feedTiger(tiger, food){
  tiger.hungry = nice.Switch(food)
    .meat(false)
    .default.use(name => tiger.say('I do not like ' + name) || true);
}

feedTiger(tiger, 'apple');   // tiger.hungry === true
// > I do not like apple

feedTiger(tiger, 'beef');    // tiger.hungry === false

Switch vs Function overload

Overloaded Function will search for best match while Switch will use first match.

nice.Function.Nothing(() => 1).Null(() => 2)(null);         // 2
nice.Switch.Nothing.use(() => 1).Null.use(() => 2)(null);   // 1

Besides current implementation of Switch use only first argument.

Boxes

Stateful observable components.

const { Box } = nice;
let b = Box(1);       // create box with 1 in it
b.listen(console.log) // listen for updates
b(2);                 // write value
b();                  // read value

// create Box that follows changes in b
let b2 = Box.use(b).by(n => n * 2);
// short version Box.by(b, n => n * 2);
b(3);                 // b2() === 6

// Named inputs
let square = Box()
  .Number('x', 5)
  .Number('y', 5)
  .by((x, y) => x * y);

square();                  // 25
square.x(10).y(b)();       // 30

Calling mapping on box will create new box that follows changes in the original.

const a = nice.Box('qwe');
const b = a.concat('!').listen(console.log);
// qwe!
a('asd');
// asd!

Calling action on box will change its content.

const a = nice.Box([1, 2]).listen(console.log);
// [1, 2];
a.push(3);
// [1, 2, 3];

Html

const div = nice.Div('Normal ', 'text ')
  .I('italic ').up
  .add('normal ')
  .B('red bold').color('red').up
  .margin('10px')
  .fontSize('20px');

// browser and server
div.html
// <div style="margin:10px;font-size:20px">Normal text <i>italic </i>normal <b style="color:red">red bold</b></div>

// browser only
div.show(); // attach dom node to document.body or provided node 

Add some Boxes to handle asynchronous cases.

const { Box, Div, Switch, Nothing } = nice;

const data = Box(Nothing);

const div = Box.by(data, Switch
      .string.use(s => Div('Data: ', s))
      .default(Div('Loading...')));

div.listen(d => console.log(d.html));
// <div>Loading...</div>



data('Some data');
// <div>Data: Some data</div>


div.show(); // will create and attach dome node and update it's state according to boxes states