Kovenant utility: Recover block

Kovenant+Recover.kt

package com.mypackage

import nl.komponents.kovenant.Promise
import nl.komponents.kovenant.deferred
import nl.komponents.kovenant.functional.bind
import nl.komponents.kovenant.task
import nl.komponents.kovenant.then

/**
 *  Utilities for recovering promises.
 *  Version: 1
 */

/** Recover using a block that returns the value directly */
infix fun<V> Promise<V, Exception>.recover(block: (Exception) -> V) : Promise<V, Exception> {

    // Create pending promise
    val pending = deferred<V, Exception>()

    // Run the promise
    this success {
        pending.resolve(it)
    } fail {

        // Failed! Run the recover function
        val error = it
        task {} then { block(error) } success {
            pending.resolve(it)
        } fail {
            pending.reject(it)
        }

    }

    // Done
    return pending.promise

}

/** Recover using a block that returns a promise */
infix fun<V> Promise<V, Exception>.recoverBind(block : (Exception) -> Promise<V, Exception>) : Promise<V, Exception> {

    // Create pending promise
    val pending = deferred<V, Exception>()

    // Run the promise
    this success {
        pending.resolve(it)
    } fail {

        // Failed! Run the recover function
        val error = it
        task {} bind { block(error) } success {
            pending.resolve(it)
        } fail {
            pending.reject(it)
        }

    }

    // Done
    return pending.promise

}