MetaCall Polyglot REPL

This repository implements a Polyglot REPL which shares the state of the meta-object protocol between the REPLs. Using the Polyglot REPL, you can share state between multiple languages through their individual REPL and mix code straight from your terminal.


The high-level api.js provided in the src provide five functions:

  • initialize: To initialize the Polyglot REPL
  • select: To select the individual language REPL; Currently Python (py) and JavaScript (node) are supported.
  • execute: To execute a line, function or module after a REPL has been selected.
  • destroy: Destroy the REPL and exit gracefully.
  • available: Check all the available REPLs.

The cli.js provided in the src provides a way to develop your own REPLs and execute code straight from the command line. You can sutomize the existing REPL or define a new one.

The entry script index.js provides an abstraction over the usage of the high-level APIs defined above through the following commands:

  %repl <tag>: Switch from different REPL (available tags: node py)
  %inspect: Show available functions
  %available: Show available REPLs
  %eval <tag> <code>: Load inline code, useful for loading inter-language functions for the REPL
  %load <tag> <file_0> <file_1> ... <file_N>: Load a file, useful for loading inter-language functions for the REPL
  %exit: Finalizes the REPL


  1. Install MetaCall:

    curl -sL | sh
  2. For running it:

    metacall index.js