Keywords Reference

NullScript provides fun, expressive alternatives to standard JavaScript keywords while maintaining full compatibility.

Core Language Keywords

Functions and Variables

NullScript	JavaScript	Example
run	function	run greet(name) { ... }
fixed	const	fixed PI = 3.14159;
let	let	let counter = 0;
var	var	var legacy = "old";

Control Flow

NullScript	JavaScript	Example
whatever	if	whatever (condition) { ... }
otherwise	else	otherwise { ... }
since	for	since (item of items) { ... }
when	while	when (condition) { ... }
switch	switch	switch (value) { ... }
case	case	case "value":
done	default	done:
stop	break	stop;
keepgoing	continue	keepgoing;

Modules

NullScript	JavaScript	Example
use	import	use fs from 'fs';
share	export	share { myFunction };

Error Handling

NullScript	JavaScript	Example
test	try	test { ... }
grab	catch	grab (error) { ... }
atLast	finally	atLast { ... }
trigger	throw	trigger new Error();

Classes and Objects

NullScript	JavaScript	Example
model	class	model MyClass { ... }
__init__	constructor	__init__() { ... }
inherits	extends	model Child inherits Parent
fresh	new	fresh MyClass();
self	this	self.property
parent	super	parent.method();
forever	static	run forever method() { ... }

Async Programming

NullScript	JavaScript	Example
later	async	run later fetch() { ... }
hold	await	let data = hold fetch();

Boolean Values

NullScript	JavaScript	Example
yes	true	fixed isValid = yes;
no	false	fixed isValid = no;

Other Keywords

NullScript	JavaScript	Example
remove	delete	remove obj.property;
what	typeof	what value
kind	instanceof	whatever (obj kind Array) { ... }
inside	in	whatever ("key" inside obj) { ... }
part	of	since (item part items) { ... }
nothing	void	nothing 0
using	with	using (obj) { ... }
freeze	debugger	freeze;
pause	yield	pause value;
getter	get	getter property() { ... }
setter	set	setter property(value) { ... }

Examples

Variable Declarations

// Constants
fixed name = "Alice";
fixed age = 25;
fixed skills = ["JavaScript", "Rust", "NullScript"];

// Variables
let score = 0;
let isPlaying = yes;

// Legacy variables (avoid when possible)
var oldStyle = "not recommended";

Function Definitions

// Regular function
run calculateArea(length, width) {
  return length * width;
}

// Arrow function (same syntax as JavaScript)
fixed multiply = (a, b) => a * b;

// Async function
run later fetchUserData(id) {
  let response = hold pull(`/api/users/${id}`);
  return hold response.json();
}

// Class method
model Calculator {
  run add(a, b) {
    return a + b;
  }

  run forever multiply(a, b) {
    return a * b;
  }
}

Control Flow Examples

// Conditional statements
whatever (age moreeq 18) {
  speak.say("You can vote!");
} otherwise whatever (age moreeq 16) {
  speak.say("You can drive!");
} otherwise {
  speak.say("You're still young!");
}

// Loops
since (let i = 0; i less 10; i++) {
  speak.say(`Count: ${i}`);
}

since (fixed item part ["apple", "banana", "cherry"]) {
  speak.say(`Fruit: ${item}`);
}

// While loop
let count = 0;
when (count less 5) {
  speak.say(`Count: ${count}`);
  count++;
}

Error Handling

run safeDivision(a, b) {
  test {
    whatever (b is 0) {
      trigger fresh fail("Cannot divide by zero!");
    }
    return a / b;
  } grab (error) {
    speak.scream(`Error: ${error.message}`);
    return null;
  } atLast {
    speak.say("Division operation completed");
  }
}

Compatibility Notes

• All NullScript keywords compile to their exact JavaScript equivalents
• You can mix NullScript and JavaScript syntax in the same file
• The transpiler only replaces NullScript keywords, leaving everything else unchanged
• Output JavaScript is always clean and readable