Compiler Status

Run is in active development. The compiler can compile and run simple programs through C code generation.

Pipeline Status

Component	Status
Lexer	Complete
Parser	Complete
Naming conventions	Complete
Name resolution	Complete
Type checking	In progress
IR lowering	Complete
C code generation	Complete
Runtime library	MVP
Standard library	Not started

Compiler Architecture

The compiler is written in Zig 0.15 and follows a traditional pipeline:

Source (.run) → Lexer → Token stream → Parser → AST → Name Resolution → Type Check → IR → C codegen

Source Files

File	Purpose
`main.zig`	CLI entry point and command dispatch
`token.zig`	Token types (~90 variants), keyword map, display names
`lexer.zig`	Single-pass stateless scanner
`parser.zig`	Recursive descent parser with precedence climbing
`ast.zig`	Flat AST representation (node array + extra_data)
`naming.zig`	Naming convention enforcement
`resolve.zig`	Name resolution and scope analysis
`symbol.zig`	Symbol table types
`typecheck.zig`	Type checking pass
`types.zig`	Type representation
`diagnostics.zig`	Rust-style diagnostic reporting with annotations
`lower.zig`	AST-to-IR lowering
`ir.zig`	Intermediate representation
`codegen_c.zig`	C code generation backend
`driver.zig`	Compilation pipeline orchestration

Diagnostics

The compiler produces Rust-style error messages with source context, caret annotations, and contextual help. All compilation phases (lexer, parser, naming, name resolution, type checking, ownership, constant folding) use a unified diagnostic system.

Features:

Source context — errors show the relevant source line with carets under the error span
Labels — concise caret-line labels distinct from the full error message
Annotations — chained notes, help, and hint messages after the primary error
“Did you mean?” — fuzzy matching suggests corrections for undefined references and struct fields
“First defined here” — duplicate definitions and immutable reassignment show the original declaration
Fix suggestions — naming violations suggest the corrected name; immutable reassignment suggests var
Keyword migration — users from Go (func), JavaScript (function), Python (def), or C++ (const) get targeted help
Semicolon detection — stray semicolons produce a clear error explaining Run uses newlines
Error count summary — compilation ends with “aborting due to N previous errors”
Color support — ANSI colors in terminal output, disabled with --no-color

Example output:

error: cannot assign to immutable variable 'x'
 --> main.run:5:5
  |
5 |     x = 10
  |     ^ cannot assign here
  |
  = note: defined as immutable here
 --> main.run:3:5
  |
3 |     let x = 42
  |     --- defined as immutable here
  |
  = help: consider using 'var' instead of 'let' if you need to reassign
error: aborting due to 1 previous error

Getting Involved

This is a great time to contribute — the language design is taking shape, and there are significant pieces to build. Check the GitHub Issues for open tasks.