Noel Rappin Writes Here

Previously in what what I guess is now “The Argument Trilogy”, we talked about: Positional Arguments Keyword Arguments And now the trilogy now comes to its inevitable conclusion with “Return of The Jedi” block arguments. In the interest of keeping this thing within the plausible word count of a newsletter, we’re not going to talk about what blocks are or the way blocks behave here, that’ll be a future Better Know, but we do need to talk about block syntax.

Last time on Better Know A Ruby Thing, we covered positional arguments, and now we’re going to move on to keyword arguments. I really did think this was going to be shorter than the last one, and then I got to the conversion between keyword and positional arguments, and then… well, it’s not shorter. (I know I said the next newsletter was going to be Conway’s Law, that’s coming, but this one moved along faster…)

Ruby has three ways to pass information from a method call to a method definition: positional arguments, keyword arguments, and block arguments. Each of these ways has: A syntax to declare an argument of that type in a method definition A syntax to declare an argument of that type in a method call A class that can can be used to convert arbitrary objects into and out of method calls A text marker that is associated with that kind of argument, *, **, or &.