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REPL

The lde repl command starts an interactive LuaJIT shell.

The shell runs in the lde environment. The require() function finds the project dependencies. lde run uses the same environment.

To start the REPL

  1. Open a terminal.
  2. Go to the project directory.
  3. Run this command:
lde repl

When you start the REPL in a package, lde does these steps:

  1. Build the package.
  2. Install the package dependencies.
  3. Add target/ to the module paths.

The prompt shows this information:

lde repl — LuaJIT interactive shell
Type exit() or press Ctrl+C to quit.

Project: my-package (/path/to/my-package)
> require("my-package.lib.helper")
= <table>

When you start the REPL outside a package, the shell opens in a plain LuaJIT state.

To edit a line

The REPL has a built-in readline function. This function is written in pure Lua. It does not need external software.

The REPL supports these functions:

These functions operate on POSIX and Windows terminals.

To complete a word

Press Tab after a prefix. The REPL completes variable and field names.

Completion covers globals and table fields, including dotted paths:

> json.e<Tab>      →  json.encode

json.e completes to json.encode.

To enter a multi-line statement

When a statement is not complete, the prompt shows .... The REPL keeps the statement in a buffer until it is complete:

> local function greet(name)
>>   return "hello " .. name
>> end
> greet("world")
= "hello world"

Declarations stay in the shell between lines. local function and const declarations become globals. They stay available on the next line:

> const retries = 5
> retries += 1
> retries
= 6

Results

The REPL shows the result of an expression. The result has the prefix =. The REPL shows tables with indentation. It detects circular references:

> { x = 1, nested = { y = 2 } }
= {
    x = 1,
    nested = {
      y = 2
    }
  }

To exit

Do one of these actions:

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