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import { Context } from './context.ts'import type { ErrorHandler, NotFoundHandler } from './hono.ts'
// Based on the code in the MIT licensed `koa-compose` package.export const compose = <C>(  middleware: Function[],  onError?: ErrorHandler,  onNotFound?: NotFoundHandler) => {  return async (context: C, next?: Function) => {    let index = -1    return dispatch(0)    async function dispatch(i: number): Promise<C> {      if (i <= index) {        return Promise.reject(new Error('next() called multiple times'))      }      let handler = middleware[i]      index = i      if (i === middleware.length && next) handler = next
      if (!handler) {        if (context instanceof Context && context.finalized === false && onNotFound) {          context.res = await onNotFound(context)        }        return Promise.resolve(context)      }
      return Promise.resolve(handler(context, () => dispatch(i + 1)))        .then(async (res: Response) => {          // If handler return Response like `return c.text('foo')`          if (res && context instanceof Context) {            context.res = res          }          return context        })        .catch((err) => {          if (context instanceof Context && onError) {            if (err instanceof Error) {              context.res = onError(err, context)            }            return context          } else {            throw err          }        })    }  }}