message: feat(case): improve equals
diff: @@ -8,7 +8,7 @@ export interface CaseBrand {
  [CaseBrand]: string[]
  }
  -export function isCase(self: unknown): self is CaseBrand {
  +export function hasCaseBrand(self: unknown): self is CaseBrand {
  return typeof self === "object" && self != null && CaseBrand in self
  }
  @@ -64,7 +64,7 @@ export const Case: {
  if (this === that) {
  return true
  }
  - if (isCase(that)) {
  + if (that instanceof this.constructor) {
  const kthat = that[CaseBrand]
  const len = kthat.length
  