linguist/samples/Golo/decorators.golo

# Copyright 2012-2014 Institut National des Sciences Appliquées de Lyon (INSA-Lyon)
# 
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# 
#     http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

module samples.Decorators

import java.util.LinkedList

function simple_decorator = |func| {
  return |a,b| -> func(a+1,b+1)
}

@simple_decorator
function simple_adder = |x,y| -> x + y

function decorator_with_params = |param1, param2|{
  return |func| {
    return |a,b| -> func(a+param1,b+param2)
  }
}

@decorator_with_params(10,2)
function parametrized_adder = |x,y| -> x + y

function generic_decorator = |func| {
  return |args...| {
    println("number of params : "+args: length())
    return func: invokeWithArguments(args)
  }
}

@generic_decorator
function generic_adder0 = -> 42

@generic_decorator
function generic_adder1 = |x| -> x

@generic_decorator
function generic_adder2 = |x,y| -> x + y

@generic_decorator
function generic_adder3 = |x,y,z| -> x + y + z

function list_sum_decorator = |func| {
    return |this| -> func(this) - 8
}

augment java.util.List {

  @list_sum_decorator
  function sum = |this| {
    var acc = 0
    foreach elem in this {
        acc = acc + elem
    }
    return acc
  }
}

function main = |args| {
  println(simple_adder(10,30))
  println(parametrized_adder(10,20))
  println(generic_adder0())
  println(generic_adder1(42))
  println(generic_adder2(20,22))
  println(generic_adder3(10,12,20))
  let list = LinkedList()
  list: add(5)
  list: add(10)
  list: add(15)
  list: add(20)
  println(list: sum())
}