# MatchAst.Prefixed

A Match AST node that structurally prefixes nested cases.

## Signatures

```ts
interface Prefixed {
    type: "prefixed";
    matches: ReadonlyArray<MatchAst>;
    prefix: RouteAst;
}
```

## Why

Nested route tables can be mounted without rewriting each child route.

## Ownership and lifetime

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

## Property: matches

The ordered child matcher nodes wrapped by this boundary.

## Property: matches: Why

Order is preserved for candidate and guard fallthrough.

## Property: matches: Ownership and lifetime

The prefix boundary retains this ordered child array by reference and applies the prefix only
during structural compilation.

## Property: prefix

The Route AST prepended to nested matcher cases.

## Property: prefix: Why

Prefixing remains structural and participates in schema/path compilation.

## Property: prefix: Ownership and lifetime

The prefix Route AST is retained by reference and owns no decoded parameter state.

## Property: type

The discriminant identifying this AST variant.

## Property: type: Why

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