[GROOVY-7956] Provide an AST transformation which improves named parameter support

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.5.0-beta-3
• Component/s: GEP
• Assignee: Paul King
• Reporter: Graeme Rocher
• Created: 04/Oct/16 12:52
• Updated: 06/Mar/18 23:25
• Resolved: 20/Feb/18 02:36

Description

In order to aid static compilation for builders we have @DelegatesTo which allows statically compiled code to know what the delegate of a closure is.

This proposal is to allow @DelegatesTo on Map types such that IDEs and the static compiler can resolve the target type the named arguments are to be used on.

For example:

class Farm {
     void animal(@DelegatesTo(Animal) Map arguments, @DelegatesTo(AnimalBuilder) Closure callable) {
             def animal = new Animal(arguments)
             // handle closure
    }
} 

class Animal { String name }

The following code would then fail to compile :

def farm = new Farm()
// compilation failure, no name property on Animal
farm.animal(nam: "Dog")  { 
}

It would then be down to IDEs to also provide support for code completion etc.

Issue Links

• links to: GitHub Pull Request #664