Development

Development

NXL is developed incrementally. Each meaningful language feature should be considered across all compiler/runtime layers.

For example, adding + requires:

Lexer
  ↓
TokenType::Plus
  ↓
Parser
  ↓
Expression::Binary
  ↓
Interpreter
  ↓
Runtime Value

The lexer recognizes +. The parser understands where it belongs. The AST represents the operation. The interpreter evaluates it. The runtime provides the resulting value.

Build

cargo build

Optimized build

cargo build --release

Check

cargo check

Run

cargo run -- examples/hello.nxl

Testing

NXL will eventually have tests at multiple levels.

Lexer tests

Test:

source → tokens

For example, let x = 10 should produce:

LET
IDENTIFIER
EQUAL
NUMBER

Parser tests

Test:

tokens → AST

For example:

a + b * 2

must produce:

a + (b * 2)

Interpreter tests

Test:

AST → runtime result

For example:

let x = 10
print(x)

should produce:

10

Integration tests

Eventually:

.nxl file
   ↓
NXL CLI
   ↓
complete execution
   ↓
expected stdout

Git workflow

Each meaningful feature should have its own commit.

Examples:

git add src/runtime.rs
git commit -m "feat: add NXL runtime value types"

git add src/environment.rs
git commit -m "feat: add NXL environment and scope handling"

git add src/interpreter.rs
git commit -m "feat: add initial NXL interpreter"

git commit -m "feat: add print builtin"

This makes the project history useful for understanding how the language evolved.