ladybird/Base/usr/share/man/man1/js.md
Sergey Bugaev db4da68618 Base: Add a man page for js(1)
This also changes --ast-dump to --dump-ast, because I like it better
and that is what the variable is actually called.
2020-03-26 08:18:08 +01:00

1 KiB

Name

js - evaluate JavaScript

Synopsis

$ js [options...] [script.js]

Description

js evaluates JavaScript programs using the LibJS engine. If you pass it a path to a script file, it will execute that script. Otherwise, it enters the Read-Eval-Print-Loop (REPL) mode, where it interactively reads pieces (usually, single lines) of code from standard input, evaluates them in one shared interpreter context, and prints back their results. This mode is useful for quickly experimenting with LibJS.

Options

  • -A, --dump-ast: Dump the Abstract Syntax Tree after parsing the program.
  • -l, --print-last-result: Print the result of the last statement executed.
  • -g, --gc-on-every-allocation: Run garbage collection on every allocation.

Examples

Here's how you execute a script:

$ js ~/js/type-play.js

And here's an example of an interactive REPL session:

$ js
> function log_sum(a, b) {
.     console.log(a + b)
. }
[object ScriptFunction]
> log_sum(35, 42)
77
undefined