Compiler

The package lives under a7/. The CLI entry point is a7.cli:main, exposed as uv run a7 after uv sync.

Pipeline

1. Tokenize source 2. Parse into AST 3. Resolve names and imports 4. Type check 5. Validate language invariants 6. Plan safety obligations 7. Preprocess AST for backend emission 8. Emit Zig 9. Let Zig build the native binary

Failures in tokenization, parsing, semantic validation, code generation, and internal errors have stable exit stages for tool usage.

CLI modes

Mode	Purpose
compile	Emit Zig (default)
tokens	Show lexer output
ast	Show parsed structure
semantic	Run semantic checks
pipeline	Full pipeline without writing a file
doc	Emit compiler documentation output

Add --format json for machine-readable output.

Exit codes

Code	Stage
0	Success
2	Usage error
3	I/O error
4	Tokenize error
5	Parse error
6	Semantic error
7	Codegen error
8	Internal error

Safety stance

A7 rejects direct recursion, mutual recursion, and local function-pointer alias-cycle recursion. Compiler internals also avoid recursive AST traversal.

The safety layer focuses on compile-time checks for:

• narrowing casts
• division and modulo denominator checks
• indexing and slicing bounds
• nil reference use
• direct use after del

These checks are compiler guarantees, not an OS sandbox.

Zig backend

The Zig backend targets Zig 0.16.0. Generated Zig should be readable, preserve source structure where practical, and remain single-file even when A7 imports multiple input files.

Debug and release artifact builders verify generated source and binaries. See Release for artifact gate commands.