As mentioned in one of the comments, PCL does good overall coverage of the condition system but does not go in depth enough for my taste; it is a book for teach

As mentioned in one of the comments, PCL does good overall coverage of the condition system but does not go in depth enough for my taste; it is a book for teaching CL, not the condition system, after all. It does not describe any applications or use cases of the condition system that do not strictly serve exception handling, and it does not show the internal construction of the condition system, especially from the approach of starting with nothing but most basic language tools which are dynamic variables, means of transferring control, closures, functions, classes, and variables.