MatchAst.Layer · API reference

Import

import { MatchAst } from "@typed/router/AST";

Access MatchAst.Layer through the imported MatchAst export. Its declaration below describes the member.

interface Layer {
    type: "layer";
    matches: ReadonlyArray<MatchAst>;
    deps: ReadonlyArray<AnyLayer>;
}

Dependencies can be prepared, committed, rolled back, and finalized with candidate selection.

Layer describes plain readonly AST data. Routes and Matchers retain the concrete nodes they receive by reference; the type itself owns no resource.

The Effect Layers attached to a matcher subtree.

Candidate services and their failures stay explicit during preparation and rollback.

Layer values are retained by identity. The executor’s Layer manager, not the AST, owns their acquired child Scopes and rollback.

The ordered child matcher nodes wrapped by this boundary.

Order is preserved for candidate and guard fallthrough.

The Layer boundary retains this ordered child array by reference so compilation preserves same-path candidate fallthrough.

The discriminant identifying this AST variant.

Exhaustive switches can interpret syntax without instanceof checks or hidden classes.