Groogy

class Boleite::GUI
  class Window < Container
    # ...

    Cute.signal header_drag(pos : Vector2f)

    def initialize
      # ...

      state_change.on &->update_header_size

Groogy

def fetch_method(klass : U) forall U
  comp = fetch_method? klass # Return type is BaseClass | Nil
  # I want to return with the type provided to find
end

Groogy

module CrystalClear
  macro included
    def test_invariant_contracts(method="")
      {% verbatim do %}
      {% for c in Contracts::INVARIANTS %}
        {% str = c[0]; condition = c[1] %}
        test = CrystalClear.perform_test(self) {{condition}}
        if !test
          Contracts.on_contract_fail(:invariant, {{str}}, {{@type}}, method)
        end

Groogy

abstract class Trashman::BaseRecord
  abstract def callstack : CallStack
  abstract def allocations : Uint64
  abstract def deallocations : Uint64
  abstract def untrack : Void
  abstract def type_str : String
end

module Trashman::Statistics
  @@records = [] of BaseRecord