Tail recursion in Groovy

Groovy ships with a limited form of tail recursion via a trampoline mechanism. Here, I expand on the existing trampoline to add a cleaner, more intuitive interface. This extension has two parts: a Java class and a new Object method (read: global function).

A Java class:

import groovy.lang.Closure;
// loop/recur

class RecursionWrapper {
    private Closure<object> _target;

    public RecursionWrapper(Closure<object> target) {
     _target = target;
    }
    
    public Object recur() {
        return _target.trampoline();
    }
    public Object recur(Object a) {
        return _target.trampoline(a);
    }
    public Object recur(Object... a) {
        return _target.trampoline(a);
    }
}

A global function:

// loop/recur

Object.metaClass.loop = {closure->
 def cln = closure.clone()
 def trCln = cln.trampoline()
 def rw = new RecursionWrapper(trCln)
 cln.delegate = rw
 trCln
}