net.liftweb.common.LoanWrapper.scala Maven / Gradle / Ivy
/*
* Copyright 2006-2010 WorldWide Conferencing, LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.liftweb {
package common {
/**
* This trait defines the principle contract for function objects that
* wrap the processing of HTTP requests by Lift while utilizing the preestablished
* request-local scope.
*/
trait CommonLoanWrapper {
/**
* Implementations of this method may either call f to continue processing
* the wrapped call as normal, or may ignore f to entirely replace the
* wrapped call with a custom implementation
* @param f the delegate which provides processing by the underlying framework
*/
def apply[T](f: => T): T
}
object CommonLoanWrapper {
/**
* If you have a List of LoanWrappers, apply them and then the functions
*/
def apply[T, LWT <: CommonLoanWrapper](lst: List[LWT])(f: => T): T = lst match {
case Nil => f
case x :: xs => x.apply(this.apply(xs)(f))
}
}
}
}