Called after resolution ends (either successfully or with an error). By default, prints a newline.

@return [void]

Called before resolution begins.

@return [void]

Conveys debug information to the user.

@param [Integer] depth the current depth of the resolution process. @return [void]

Whether or not debug messages should be printed. By default, whether or not the `MOLINILLO_DEBUG` environment variable is set.

@return [Boolean]

Called roughly every {progress_rate}, this method should convey progress to the user.

@return [void]

The {IO} object that should be used to print output. `STDOUT`, by default.

@return [IO]

How often progress should be conveyed to the user via {indicate_progress}, in seconds. A third of a second, by default.

@return [Float]