Question

Why this code doesn’t work (no output)?

clo1 = {
    for(int i =0; i<=10; i++){
        println(i);
    }
}

def thread = Thread.start { clo1 }

But this do work:

def thread = Thread.start {
    for(int i =0; i<=10; i++){
        println(i);
    }
}

Answer 1

If you want to execute clo1 in the thread you can either do

Thread.start clo1 // same as Thread.start(clo1)

or

Thread.start { clo1() }

The first one passes the closure directly to Thread.start. The second solution creates a new closure which executes clo1.

With Thread.start { clo1 } just you pass a new closure (that does nothing) to Thread.start.