elixir.2: provide new elixir implementation

Author: chrooti

IMPLS.yml

@@ -22,6 +22,7 @@ IMPL:
   - {IMPL: dart}
   - {IMPL: elisp}
   - {IMPL: elixir}
+  - {IMPL: elixir.2}
   - {IMPL: elm}
   - {IMPL: erlang, NO_SELF_HOST: 1}  # step4 silent exit on "(DO 3)"
   - {IMPL: es6}

Makefile.impls

@@ -33,7 +33,7 @@ wasm_MODE = wasmtime
 #
 
 IMPLS = ada ada.2 awk bash basic bbc-basic c c.2 chuck clojure coffee common-lisp cpp crystal cs d dart \
-	elisp elixir elm erlang es6 factor fantom fennel forth fsharp go groovy gnu-smalltalk \
+	elisp elixir elixir.2 elm erlang es6 factor fantom fennel forth fsharp go groovy gnu-smalltalk \
 	guile hare haskell haxe hy io janet java java-truffle js jq julia kotlin latex3 livescript logo lua make mal \
 	matlab miniMAL nasm nim objc objpascal ocaml perl perl6 php picolisp pike plpgsql \
 	plsql powershell prolog ps purs python2 python3 r racket rexx rpython ruby ruby.2 rust scala scheme skew sml \
@@ -125,6 +125,7 @@ d_STEP_TO_PROG =             impls/d/$($(1))
 dart_STEP_TO_PROG =          impls/dart/$($(1)).dart
 elisp_STEP_TO_PROG =         impls/elisp/$($(1)).el
 elixir_STEP_TO_PROG =        impls/elixir/lib/mix/tasks/$($(1)).ex
+elixir.2_STEP_TO_PROG =      impls/elixir.2/lib/steps/$($(1)).ex
 elm_STEP_TO_PROG =           impls/elm/$($(1)).js
 erlang_STEP_TO_PROG =        impls/erlang/$($(1))
 es6_STEP_TO_PROG =           impls/es6/$($(1)).mjs

README.md

@@ -42,7 +42,7 @@ process guide](process/guide.md) there is also a [mal/make-a-lisp
 FAQ](docs/FAQ.md) where I attempt to answer some common questions.
 
 
-**3. Mal is implemented in 89 languages (95 different implementations and 118 runtime modes)**
+**3. Mal is implemented in 89 languages (96 different implementations and 119 runtime modes)**
 
 | Language | Creator |
 | -------- | ------- |
@@ -63,7 +63,8 @@ FAQ](docs/FAQ.md) where I attempt to answer some common questions.
 | [Crystal](#crystal) | [Linda_pp](https://github.com/rhysd) |
 | [D](#d) | [Dov Murik](https://github.com/dubek) |
 | [Dart](#dart) | [Harry Terkelsen](https://github.com/hterkelsen) |
-| [Elixir](#elixir) | [Martin Ek](https://github.com/ekmartin) |
+| [Elixir](#elixir) | [Martin Ek](https://github.com/ekmartin) | [
+| [Elixir #2](#elixir2) | [Alessandro Cerruti](https://github.com/chrooti) |
 | [Elm](#elm) | [Jos van Bakel](https://github.com/c0deaddict) |
 | [Emacs Lisp](#emacs-lisp) | [Vasilij Schneidermann](https://github.com/wasamasa) |
 | [Erlang](#erlang) | [Nathan Fiedler](https://github.com/nlfiedler) |
@@ -445,6 +446,17 @@ mix stepX_YYY
 iex -S mix stepX_YYY
 ```
 
+### Elixir.2
+
+The second Elixir implementation of mal has been tested with Elixir 1.19.5 and Erlang/OTP 28.
+
+```
+cd impls/elixir.2
+STEP=stepX_YYY mix run
+# Or with readline/line editing functionality:
+STEP=stepX_YYY iex -S mix
+```
+
 ### Elm
 
 The Elm implementation of mal has been tested with Elm 0.18.0

impls/elixir.2/.credo.exs

@@ -0,0 +1,13 @@
+%{
+  configs: [
+    %{
+      name: "default",
+      checks: %{
+        disabled: [
+          {Credo.Check.Readability.ModuleDoc, []},
+          {Credo.Check.Refactor.CyclomaticComplexity, []}
+        ]
+      }
+    }
+  ]
+}

impls/elixir.2/.formatter.exs

@@ -0,0 +1,4 @@
+# Used by "mix format"
+[
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+]

impls/elixir.2/.gitignore

@@ -0,0 +1,25 @@
+# The directory Mix will write compiled artifacts to.
+/_build/
+
+# If you run "mix test --cover", coverage assets end up here.
+/cover/
+
+# The directory Mix downloads your dependencies sources to.
+/deps/
+
+# Where third-party dependencies like ExDoc output generated docs.
+/doc/
+
+# Temporary files, for example, from tests.
+/tmp/
+
+# If the VM crashes, it generates a dump, let's ignore it too.
+erl_crash.dump
+
+# Also ignore archive artifacts (built via "mix archive.build").
+*.ez
+
+# Ignore package tarball (built via "mix hex.build").
+mal-*.tar
+
+/.elixir_ls

impls/elixir.2/.iex.exs

@@ -0,0 +1 @@
+Mal.start_repl()

impls/elixir.2/Dockerfile

@@ -0,0 +1,30 @@
+FROM ubuntu:24.04
+MAINTAINER Alessandro Cerruti <whisper@chrooti.org>
+LABEL org.opencontainers.image.source=https://github.com/kanaka/mal
+LABEL org.opencontainers.image.description="mal test container: Elixir.2"
+##########################################################
+# General requirements for testing or common across many
+# implementations
+##########################################################
+
+RUN apt-get -y update
+
+# Required for running tests
+RUN apt-get -y install make python3
+RUN ln -sf /usr/bin/python3 /usr/bin/python
+
+# Some typical implementation and test requirements
+RUN apt-get -y install curl libreadline-dev libedit-dev
+
+RUN mkdir -p /mal
+WORKDIR /mal
+
+##########################################################
+# Specific implementation requirements
+##########################################################
+
+# Elixir (14)
+RUN apt-get install -y erlang-dev elixir
+
+USER 1000
+RUN mix local.hex --force

impls/elixir.2/Makefile

@@ -0,0 +1,13 @@
+.PHONY: all
+all: | deps
+	mix compile
+
+deps:
+	mix deps.get
+
+lib/steps/*.ex: all
+
+.PHONY: clean
+clean:
+	mix clean
+	rm -fr deps _build .elixir_ls

impls/elixir.2/lib/mal.ex

@@ -0,0 +1,21 @@
+defmodule Mal do
+  use Application
+
+  def start(_type, _args) do
+    if not IEx.started?() do
+      start_repl()
+    end
+
+    {:ok, self()}
+  end
+
+  def start_repl() do
+    step =
+      System.fetch_env!("STEP")
+      |> String.split("_")
+      |> Enum.map_join(&String.capitalize/1)
+
+    module_name = Module.safe_concat([Mal, step])
+    module_name.start()
+  end
+end