strictjson

type Options struct {
	// Hidden returns the keys of struct type t the calling instance
	// hides (a feature-profile-gated slot). A hidden key is refused
	// exactly as an unknown one and never appears in valid_keys or a
	// suggestion. Nil hides nothing.
	Hidden func(t reflect.Type) []string

	// AllowMeta tolerates a `_meta` key at the document root (the
	// examples sidecar block), as the lenient decode always did. A
	// rendered template leaves it false: there `_meta` is refused.
	AllowMeta bool

	// DocumentOrder reports the first unknown key in document order,
	// depth first — the key encoding/json's DisallowUnknownFields names
	// (a rendered template's contract). The default reports an object's
	// own keys before any child's, so a request root's misspelled slot
	// is refused before anything nested inside it (descx.SlotRefusal's
	// order).
	DocumentOrder bool

	// Aliases returns known misnomers for struct type t's keys — an
	// unknown key mapped to the valid key no edit distance would reach
	// (a synth correlation's `correlation` is `rho`). The refusal
	// suggests the alias ahead of the nearest-key guess
	// (UnknownFieldErrorAliased). Nil aliases nothing.
	Aliases func(t reflect.Type) map[string]string
}

type Unknown struct {
	// Path is the object's location relative to the innermost request
	// (Location resets it): "" for that request's root, else e.g.
	// "sort[0]" or "crosstab.cell".
	Path string
	// FullPath is the object's location from the document root.
	FullPath string
	// Keys are the unrecognised (or hidden) keys, sorted.
	Keys []string
	// First is the object's first unrecognised key in document order.
	First string
	// Valid are the object's visible keys, in declaration order.
	Valid []string
	// Type is the object's struct type.
	Type reflect.Type
	// LocationKey / LocationIndex name the nested request Path is
	// relative to (LocationRequest / LocationFit / LocationStage and
	// its index); LocationKey is "" outside a nested request.
	LocationKey   string
	LocationIndex int
	// Aliases are Options.Aliases for Type, carried to the refusal.
	Aliases map[string]string
}