Slicing might accomplish the same goal:
def list = ['Simple', 'list', 'with', 5, 'items']
assert list[0..1] == ['Simple', 'list']
Pergunta
The take and drop methods were added to the list object in groovy v 1.8.1, and work like this:
def list = ['Simple', 'list', 'with', 5, 'items']
assert list.take(2) == ['Simple', 'list']
I only have v 1.8.0 available to me. How can I reimplement my own version of list.take(2) using Groovy v1.8.0 ?
Is it possible to do something like:
def list = ['Simple', 'list', 'with', 5, 'items']
def limit = 2
assert list['0..'+limit] == ['Simple', 'list']
When I try this I get an exception.
Solução
Slicing might accomplish the same goal:
def list = ['Simple', 'list', 'with', 5, 'items']
assert list[0..1] == ['Simple', 'list']
Outras dicas
you could do it the way groovy does it
public static <T> List<T> take(List<T> self, int num) {
if (self.isEmpty() || num <= 0) {
return createSimilarList(self, 0);
}
if (self.size() <= num) {
List<T> ret = createSimilarList(self, self.size());
ret.addAll(self);
return ret;
}
List<T> ret = createSimilarList(self, num);
ret.addAll(self.subList(0, num));
return ret;
}
the method createSimilarList
can be found here
Along the same lines as GargantuChet's answer, you can slice it, but using an exclusive range:
List.metaClass.take { n ->
def len = [n,delegate.size()].min()
delegate[0..<len]
}
assert [1,2,3,4].take(2) == [1,2]
assert [1,2].take(2) == [1,2]
assert [1].take(2) == [1]
assert [].take(2) == []