: Xlerb is Forth Flavoured Erlang! ;

: maths [
  : area square constants:pi * ;

  : 0 factorial drop 1 ;
  : _ factorial dup 1 - factorial * ;

  : square dup * ; private
] ; module

Modules and Matching

A fully-fledge module system, and pattern matching right off the stack.

: ping-server
  [ : _from :ping -> drop ! :pong send ;
    : _from     _ -> drop drop ;
  ] receive
  ping-server ;

Process-to-process Message Passing

Stack-oriented communication with a somewhat usable syntax!

[0]> [ping-server] spawn
[1]> ! :ping send
[0]> whatever receive .
:pong

Fearless concurrency

All code runs in isolated processes. Spin up a server, a timer, whatever!

[0]> [1 2 4] [Enum max 1] elixir .
4
[0]> 5 3 [math pow 2] erlang dup .
125.0

Elegant Interop

Call any Erlang/Elixir function with an MFA triple.

[0]> :ok 100 &{&2, &1} pack .
{:ok, 100}
[0]> :name :joe %{&2 => &1} pack .s
%{name: :joe}
[1]> &%{name: &1} unpack .
:joe

Stack packing

Using familar syntax, pack and unpack terms onto the stack

Finally, concurrent multi-process concatenative programming on the BEAM!

Xlerb is a compiled, concatenative stack-based language which takes the experience of writing Joy/Forth and shoehorns it onto rock-solid runtime that powers Erlang, Elixir and Gleam.

The solution to a problem no one had, an answer to a question no one asked - the expressivity and maintainability of Forth/Joy with the unshakable reliability of the Erlang Runtime System!