Tap inside a monadic chain.Given a function f, tap<M> returns a new function which performs f on its argument and then returns the argument lifted in the MMonad. Combined with the property that chain(m, lift<M>) == m, this provides a way of executing an action inside a monadic chain without influencing its overall result. This is useful to e.g. insert debug statements or perform actions that are not tied to the chain but that need to be executed inside of it. More...
Louis Dionne 2013-2016 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)