Errata for Programming Ruby 3

#30570: you should add the "Ruby One-Click Installer for Mac OSX" to your list of osx ruby distributions. see the project on rubyosx.com -- furthermore, there is a one-click installer for ruby 1.9 for osx in development, soon to be released on rubyosx.com.

(Dave says: I will when it supports 1.9)--Matthias Tarasiewicz

#33198: It looks like you're trying to keep a clean set of numbered "tutclasses_##.rb" files. But it seems a little strange that we have a java class here in an .rb file.--Charlie O'Keefe

#33199: It looks like you're trying to have a cleanly numbered set of "tutclasses_##.rb" files, but in the example on this page we're calling the files by one set of names in the text (book_in_stock.rb, csv_reader.rb, and stock_stats.rb) and another set of names in the caption starting each code sample.--Charlie O'Keefe

#34322: > Then, as you fill in the code, the specs mutate into tests that validate your code meets your expectations.

Revise 'meets your expectations.' Pehaps 'which meets your expectations.'--Emiel van de Laar

#34317: you says "Class BasicObject does not include the method define_method".
but you can call it because the class of BasicObject is Class class, then Class class is a subclass of Module class, which include define_method.
I think instance_exec is used because define_method is private, for which you can not specify a receiver.--Kyo Endo

#32757: In the table of contents, the “Array” and similar sections are on the same level than the “Built-in Classes and Modules” section, thus, it is impossible to fold all built-in classes to show only the standard library classes.

The built-in classes should be a subsection of the “Built-in Classes and Modules” section.

Also, the naming in table of contents is somewhat strange, e.g. “Array” is named in the toc “4-1Array”.

In case something is unclear, you can mail me at giga@le-pec.org.

Thanks for your hard work.--Jean-Philippe Garcia Ballester

#30437: Chapter 28 (extending ruby) doesn't discuss the treading model in 1.9, and the big VM lock. I think this is a big change, and should be addressed, so people can write better extensions.

Excerpt from ko1:
See rb_thread_blocking_region() in thread.c.

rb_thread_blocking_region(
rb_blocking_function_t *func, void *data1,
rb_unblock_function_t *ubf, void *data2)

func() is your function which you want to do without GL. YARV
release GL and call func(). If func() returned, YARV acquire GL and
continue ruby program.

ubf (unblocking function) is called when another thread interrupts
this thread with Thread#kill, or main thread exits. You must set
ubf as interrupt function for func(). You must write ubf or ruby
will not exit until func() ends.--Victor Marius Costan