error-codes

Error Codes — Directory Index

This directory contains one file per SuperJS diagnostic code. The authoritative registry (full table with severity, category, short message, and owning stage for every code) lives in specs/error-codes.md. This file is a navigational index only.

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P Series — Parser (Stage 1)

Emitted by the SuperJS parser during syntactic analysis. All parser diagnostics have severity error.

Code	Short message	File
SJS-P001	Unexpected token	SJS-P001.md
SJS-P002	Unexpected end of file	SJS-P002.md
SJS-P003	Invalid syntax in type annotation	SJS-P003.md
SJS-P004	Invalid sum type declaration	SJS-P004.md
SJS-P005	Invalid match expression	SJS-P005.md
SJS-P099	Too many parse errors; recovery abandoned	SJS-P099.md

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E Series — Type Errors (Stage 0 / Stage 1 / Stage 2)

Emitted by the type checker. Codes marked Stage 0 are already emitted by the prototype.

Code	Short message	File
SJS-E001	Null or undefined assigned to non-nullable type T	SJS-E001.md
SJS-E002	Type mismatch: expected T, found U	SJS-E002.md
SJS-E003	Property access on possibly-null value	SJS-E003.md
SJS-E004	any is not a valid type in SJS; use dynamic	SJS-E004.md
SJS-E005	Intersection type A & B is not allowed; use interface extension	SJS-E005.md
SJS-E006	Mapped type is not allowed in SJS	SJS-E006.md
SJS-E007	Match expression is not exhaustive: missing variant V	SJS-E007.md
SJS-E008	Conditional type T extends U ? A : B is not allowed	SJS-E008.md
SJS-E009	infer keyword is not allowed in SJS	SJS-E009.md
SJS-E010	TypeScript enum is not allowed; use sum types	SJS-E010.md
SJS-E011	Non-null assertion ! is not allowed; use narrowing	SJS-E011.md
SJS-E012	namespace is not allowed; use ES modules	SJS-E012.md
SJS-E013	with statement not allowed (SJS is always strict mode)	SJS-E013.md
SJS-E014	Private or protected member not accessible from this scope	SJS-E014.md
SJS-E015	Cannot narrow an access modifier on an overriding method or property	SJS-E015.md
SJS-E016	Cannot instantiate an abstract class directly with new	SJS-E016.md
SJS-E017	Circular import detected — module graph contains a cycle	SJS-E017.md
SJS-E018	Top-level await used outside an ES module context	SJS-E018.md
SJS-E019	Unknown JSX element type — identifier not in scope or not a valid component	SJS-E019.md

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W Series — Warnings (Stage 0 / Stage 1 / Stage 2)

Emitted by the type checker or compiler pipeline for conditions that are not hard errors but likely indicate problems.

Code	Short message	File
SJS-W001	Implicit dynamic — unannotated position in --strict mode	SJS-W001.md
SJS-W002	dynamic value assigned to a typed position without a narrowing check	SJS-W002.md
SJS-W003	Unreachable match arm — earlier arm already covers this variant	SJS-W003.md
SJS-W004	Reserved or future SJS keyword used as an identifier	SJS-W004.md
SJS-W005	Explicit public modifier is redundant — class members are public by default	SJS-W005.md
SJS-W006	Excess property on a fresh object literal assigned to a typed position	SJS-W006.md
SJS-W007	Missing key prop on JSX element in a list or iterator context	SJS-W007.md
SJS-W008	Implicit switch fallthrough between non-empty case clauses	SJS-W008.md
SJS-W009	Unreachable code following a terminator statement	SJS-W009.md
SJS-W010	catch binding not typed as Error or unknown	SJS-W010.md
SJS-W012	BiDi control character in source file	SJS-W012.md

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L Series — Lint / Security (Stage 1 / Stage 3)

Emitted by the linter (Stage 3) or the lexer for security-critical conditions (Stage 1).

Code	Short message	File
SJS-L001	Prefer const — let binding is never reassigned	SJS-L001.md
SJS-L002	Prefer let or const over var	SJS-L002.md
SJS-L003	Use === / !== — == / != performs type coercion	SJS-L003.md
SJS-L004	Prefer for…of over for…in for array and iterable iteration	SJS-L004.md
SJS-L005	debugger statement found in committed code	SJS-L005.md
SJS-L011	BiDi control character rejected	SJS-L011.md

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Notes

• Code numbers are permanent. Retired codes remain listed in specs/error-codes.md and are never reused.
• To add a new code, follow the process in the Adding New Codes section of the registry, then add the per-code .md file here and update this index.
• The superjs explain SJS-XXXX CLI command reads these files directly to render diagnostic help text in the terminal.