Closures have access to variables in their surrounding scope. These can be local variables or parameters passed to a method inside which the closure is defined. Here, we can access the name parameter and the local variable salutation in our closure:
def greeting ( name ) {
def salutation = "Hello"
def greeter = { println "$salutation , $name" }
greeter()
}
when: "we call the greeting method"
greeting("Dolly")
then:
"Hello , Dolly" == output()If the closure is defined within a class method, then the object instance fields are also available to the closure. The field member separator, shown in the following code, is also accessible within the closure:
class ClosureInClassMethodScope {
def separator = ", "
def greeting ( name ) {
def salutation = "Hello"
def greeter = { println "$salutation$separator$name" }
greeter()
}
}
given: "A class with a closure in a method"
ClosureInClassMethodScope greeter = new
ClosureInClassMethodScope...