CODEWITHSUNDEEP
groovy
Breako Breako
Breako Breako

Reputation: 6461

Possible to pass closure into spread operator

Is it possible to use a closure with the spread operator with Groovy.

e.g.

def numbers = [4,8]
def numbersPlusTen = numbers*.{it -> it + 10}

Or can the spread operator only ever work on a method or property?

Upvotes: 3

Views: 465

Answers (3)

tomasb
tomasb

Reputation: 1673

Also you can use List's each() method for even more complex operation, not just plus():

list.each({item -> item.callSomeMethod(item.getSomeProperty()+1)})

so your example with implicit arg would be:

def numbersPlusTen = []
numbers.each({numbersPlusTen << it+10})

spread operator may also be used in front:

def args = [4,8]
function f(int x, int y) {x+y}
f(*args)

Upvotes: 0

dmahapatro
dmahapatro

Reputation: 50245

Or I would just do 

def numbers = [4,8]
def numbersPlusTen = numbers*.plus(10)

if I want to add 10. :)

Upvotes: 4

Joshua Moore
Joshua Moore

Reputation: 24776

No, the spread dot operator only works on methods. However in your example you can use some meta programming to make this work.

​def numbers = [4,8]
java.lang.Integer.metaClass.something = {delegate + 10}
def numbersPlusTen = numbers*.​something()​

Upvotes: 3

Related Questions