gotojs

A delightfully evil abomination of eval() with goto(); all in global space by Dave Balmer.

It's a lightweight, low-level library that:

Introduces proper sequential programming based on line numbers, something sorely missing from JavaScript
Reduces complexity by eliminating the need for semicolons
Works exclusively in global space; no more var statements for your variables (seriously, don't use them or something may break)
Simple, direct control of code execution with goto()
Powered by eval()

Use

program = {
	10: "x = 0",
	20: "x = x + 1",
	30: "print(x)",
	40: "if (x < 10) goto(20)",
	50: "end()"
};

run();

run(line) start execution of the program at the beginning or line.
goto(line) move execution to the line specified.
print(string) prints the string to the document.body.
button(text, line) displays a button with text contents, will goto(line) when clicked.
clear() clear the screen
tron() turns the tracer on.
tron() turns the tracer off.
end() stop execution of the program.