EachWithLast.groovy

/*def imewi = Iterable.metaClass.eachWithIndex
def lmewi = List.metaClass.eachWithIndex
println imewi 
println lmewi

def iewi = Iterable.&eachWithIndex
def lewi = List.&eachWithIndex
*/
def eachWithLast = { Closure c ->
    int size = delegate.size()
    delegate.eachWithIndex { item, idx ->
        boolean last = idx == size - 1
        c(item, last)
    }
}

def cewl = { item, last ->
    println "$item is ${last ? '' : 'not '}last"
}

List.metaClass.eachWithLast << eachWithLast

[1, 2, 3].eachWithLast cewl
['a','b','c'].eachWithLast cewl

Iterable.metaClass.eachWithLast << eachWithLast

import java.nio.file.*
Path path = FileSystems.getDefault().getPath(/C:\Users\jwolf2\Desktop/);
path.eachWithLast { item, last ->
    println "$item is ${last ? '' : 'not '}last"
}