Arraylist full of functions?

Processing Coding Questions
1

I need to store a list of functions that I can execute from said array.
I also need to be able to pass them as variables.
Lambda doesn’t seem to work in processing. How can I do this?
Thanks!

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2
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3

i dont know if you have to use processing, but if you really need lambda expression try using processing as java library from another ide

4

Can you list all input parameters and all return types.

5

No inputs, all floats.

6

Sam Pottinger has done an amazing job in updating processing, not only to update to OpenJDK11, but also to support java 8 syntax in the processing ide. I’m sure he would welcome your support. Here is an example using lambda syntax in the processing ide.

lambda
lambda.png698×604 42.1 KB 

interface MyFunction {
  float calculate(float x);
}

float[] values = new float[2];

void setup() {
  // lambda expression to define the calculate method
  MyFunction doubling = (float x)->x * 2;
  values[0] = doubling.calculate(5);
  values[1] = doubling.calculate(12);
  display();
}

void display() {
  println(values[0], values[1]);
}

The code can be even more elegant in JRubyArt

attr_reader :values

def setup
  # lambda expression to define the calculate method
  doubling = ->(x) { x * 2 }
  @values = [5.0, 12.0].map { |x| doubling.call(x) }
  display
end

def display
  puts values
end
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7

Or as GoToLoop has already posted for the faint hearted see Function as argument of another function, but the update to jdk8 syntax is somewhat overdue.

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