Errors

The Node Errors API is cross-cutting behavior rather than a node:errors module. Standard error constructors are globals, while individual Node APIs create coded and system errors. Jco therefore does not resolve node:errors; Node 24 rejects that specifier as well.

Bundled code can use Error, AggregateError, DOMException, EvalError, RangeError, ReferenceError, SuppressedError, SyntaxError, TypeError, and URIError without an import. Rolldown injects @bytecodealliance/jco-std/wasi/0.2.x/node/24.x.x/errors only for constructors actually referenced by the source graph. A graph that uses none of them contains none of the adapter after bundling.

The adapter preserves the guest engine’s constructor identities, supplies portable fallbacks for missing newer constructors and V8 Error extensions, and provides the common coded/system-error core used by other jco-std Node shims. No WIT capability is required. Error classes, codes, and documented system fields are compatibility targets; exact stack frames and source positions remain engine-specific.