Lumen

Lumen is a compiled, statically checked language by Nytrix Labs. It compiles to Echo, a bytecode language that runs on its own VM. Both are written in Rust.

• SPEC.md: the Lumen language (draft). §15 lists the choices the implementation made where the spec is undecided.
• ECHO.md: the Echo bytecode format and VM.

Build

cargo build --release
cargo install --path lumen && cargo install --path echo   # optional: put them on your PATH

This builds three commands in target/release/: lumen, echovm and lumen-lsp. The VM isn't called echo because that name is a shell builtin. lumen-lsp is a language server for editors. editors/zed/ is a Zed extension that uses it (see its README).

Use

A project is a folder with a project file in it:

mkdir hello && cd hello
lumen init               # makes hello.lmnproj and main.lmn
lumen run                # compiles and runs main.lmn
lumen build              # writes hello.echo

Files in the project drag each other by the project's name: drag .decdk from hello in main.lmn loads decdk.lmn, and its functions and types are then used as decdk.greet[…].

Single files work without a project too:

lumen examples/spec13.lmn            # compile and run
lumen build examples/spec13.lmn      # write examples/spec13.echo
lumen asm examples/spec13.lmn        # show the compiled Echo as text
lumen check examples/spec13.lmn      # errors and warnings only
lumen fmt                            # tidy indentation and blank lines in every .lmn of the project
lumen fmt --check examples/*.lmn     # list files that aren't formatted (exit 1), changing nothing

echovm examples/spec13.echo          # run compiled bytecode
echovm disasm examples/spec13.echo   # bytecode → .echoasm text
echovm asm prog.echoasm -o prog.echo # .echoasm text → bytecode

Layout

Path	What
echo/src/module.rs	Echo modules and the .echo binary format
echo/src/opcode.rs	the instruction set
echo/src/vm.rs	the VM, Group methods, natives (stdout, stdin)
echo/src/asm.rs	.echoasm assembler and disassembler
lumen/src/lexer.rs, parser.rs, ast.rs	Lumen source to syntax tree
lumen/src/compiler.rs	type checking and Echo code generation, plus the built-ins push and pull
lumen/src/format.rs	the formatter behind lumen fmt and the LSP's "format document"
lumen/src/project.rs	project files, lumen init, and loading dragged files
lumen/tests/programs.rs, projects.rs	end-to-end tests
lumen-lsp/	the language server: diagnostics from the compiler, quick fixes, completion, hover
tree-sitter-lumen/	a tree-sitter grammar, for highlighting
editors/zed/	the Zed extension
examples/	example programs, each with its expected output in a .out file

Test

cargo test