Creates a validator to see if the source handler has a card they are attempting to play
Creates a validator to see if the source handler has the cards they are attempting to play
Creates a canRespond validator to test if it is the message source's turn
Creates a canRespond validator to test if the game is waiting on the source handler
Creates a merger function to remove the cards from the source handler's hand
Creates a merger function to remove the source handler from waiting
Creates a merger function to set the played trick card
Creates a simple validator using an error message
A set of utility functions that are helpful when writing event handlers