Reference

Diagnostics

Diagnostics are a first-class feature. The compiler reasons about what you were trying to express and offers a literal correction — never a stack trace.

What a diagnostic shows you

A Zornux error tells you the code, where it happened, what went wrong in plain English, and how to fix it:

text

error[ZX0103]: I expected 'end' to close this 'if' block.
  --> minor.zx:1:1
   |
 1 | if age is less than 18
   | ^ this block is still open
   |
 help: add 'end' on a new line after the last statement of the block.

Authoring rules

Speak to a beginner — "I expected…", "I could not find…", never "unexpected token".
Name what was expected and what was found, in human terms.
Offer a fix when one is unambiguous.
No internals leak — AST node names and host exceptions never appear.
One problem, one diagnostic — recovery prevents cascading noise.
Codes are forever — once shipped, a code's meaning is frozen.

Code ranges

Every code is ZX plus four digits, reserved per subsystem:

Range	Subsystem
`ZX0001–0099`	Lexer (characters, tokens, strings)
`ZX0100–0299`	Parser (grammar / structure)
`ZX0300–0399`	Semantic analysis & names
`ZX0400–0499`	Compiler
`ZX0500–0699`	Type system
`ZX0700–0899`	Runtime
`ZX0900–0999`	Classes (OOP)
`ZX1000–1099`	Standard library
`ZX1100–1199`	Web services
`ZX1200–1299`	Security
`ZX1300–1399`	Module system
`ZX1400–1499`	Package manager
`ZX1500–1599`	Testing framework
`ZX1600–1699`	Documentation generator
`ZX1700–1799`	Debugger
`ZX1900–1999`	Application entry point
`ZX2000–2099`	Structured concurrency
`ZX2100–2199`	Error recovery (try)
`ZX2200–2299`	Maps / dictionaries
`ZX2300–2399`	Async execution
`ZX2400–2499`	Data layer / ORM
`ZX2500–2599`	Enterprise application layer
`ZX2600–2699`	Configuration, secrets & environment
`ZX2700–2799`	Middleware & request pipeline
`ZX2800–2899`	Logging & observability
`ZX2900–2999`	Advanced authorization
`ZX3000–3099`	Background processing
`ZX3100–3199`	Advanced data / queries
`ZX3200–3299`	Messaging & event bus
`ZX3300–3399`	Enterprise hardening
`ZX3400–3499`	Remote package registry
`ZX3500–3599`	ORM migrations & schema evolution
`ZX3600–3699`	Native deployment & hosting
`ZX3700–3799`	Security analyzer (advisory rules ZX3701–3711)
`ZX3800–3899`	Memory safety & resource limits
`ZX3900–3999`	Profiling
`ZX4000–4099`	Static analysis (definite-assignment, reachability, type & relationship audit)

A few in the catalog

Code	Message
`ZX0002`	This text string is missing its closing quote ".
`ZX0103`	I expected 'end' to close this if block.
`ZX0104`	'repeat' needs a count followed by 'times'.
`ZX0110`	'function' is a reserved word and can't be used as a name.
`ZX0700`	I don't know what 'name' is — it was never created.
`ZX0706`	I can't divide by zero.
`ZX1205`	This value is untrusted and must be checked before it's combined with trusted text.
`ZX2504`	Validation failed — a record broke its rules.
`ZX3001`	There's no job named 'SendWelcome'.
`ZX0119`	This is nested too deeply to parse.
`ZX0957`	This property is read-only and can't be assigned.
`ZX0731`	There's no parameter named 'timeut' here. Did you mean 'timeout'?
`ZX1051`	This regular expression timed out — it backtracks too much on this input.
`ZX1316`	'internal_helper' exists in module 'users' but isn't public.

Machine-readable too

Every diagnostic also serializes to JSON (code, severity, message, file, range, help) for editor tooling and CI.