The InstructionSequence
class represents a compiled sequence of instructions for the Virtual Machine used in MRI. Not all implementations of Ruby may implement this class, and for the implementations that implement it, the methods defined and behavior of the methods can change in any version.
With it, you can get a handle to the instructions that make up a method or a proc, compile strings of Ruby code down to VM instructions, and disassemble instruction sequences to strings for easy inspection. It is mostly useful if you want to learn how YARV works, but it also lets you control various settings for the Ruby iseq compiler.
You can find the source for the VM instructions in insns.def
in the Ruby source.
The instruction sequence results will almost certainly change as Ruby changes, so example output in this documentation may be different from what you see.
Of course, this class is MRI specific.
Mixin methods for –version and –platform Gem::Command
options.
A pointer to a C union
Raised by Gem::Resolver
when a Gem::Dependency::Conflict reaches the toplevel. Indicates which dependencies were incompatible through conflict
and conflicting_dependencies
Raised when attempting to uninstall a gem that isn’t in GEM_HOME.
Raised by the DependencyInstaller when a specific gem cannot be found
UserInteraction
allows RubyGems to interact with the user through standard methods that can be replaced with more-specific UI methods for different displays.
Since UserInteraction
dispatches to a concrete UI class you may need to reference other classes for specific behavior such as Gem::ConsoleUI
or Gem::SilentUI
.
Example:
class X include Gem::UserInteraction def get_answer n = ask("What is the meaning of life?") end end
This is not an existing class, but documentation of the interface that Scheduler object should comply to in order to be used as argument to Fiber.scheduler
and handle non-blocking fibers. See also the “Non-blocking fibers” section in Fiber
class docs for explanations of some concepts.
Scheduler’s behavior and usage are expected to be as follows:
When the execution in the non-blocking Fiber
reaches some blocking operation (like sleep, wait for a process, or a non-ready I/O), it calls some of the scheduler’s hook methods, listed below.
Scheduler somehow registers what the current fiber is waiting on, and yields control to other fibers with Fiber.yield
(so the fiber would be suspended while expecting its wait to end, and other fibers in the same thread can perform)
At the end of the current thread execution, the scheduler’s method close
is called
The scheduler runs into a wait loop, checking all the blocked fibers (which it has registered on hook calls) and resuming them when the awaited resource is ready (e.g. I/O ready or sleep time elapsed).
A typical implementation would probably rely for this closing loop on a gem like EventMachine or Async.
This way concurrent execution will be achieved transparently for every individual Fiber’s code.
Hook methods are:
(the list is expanded as Ruby developers make more methods having non-blocking calls)
When not specified otherwise, the hook implementations are mandatory: if they are not implemented, the methods trying to call hook will fail. To provide backward compatibility, in the future hooks will be optional (if they are not implemented, due to the scheduler being created for the older Ruby version, the code which needs this hook will not fail, and will just behave in a blocking fashion).
It is also strongly recommended that the scheduler implements the fiber
method, which is delegated to by Fiber.schedule
.
Sample toy implementation of the scheduler can be found in Ruby’s code, in test/fiber/scheduler.rb
A base class for objects representing a C union
Socket::Option
represents a socket option used by BasicSocket#getsockopt
and BasicSocket#setsockopt
. A socket option contains the socket family
, protocol level
, option name optname
and option value data
.
Map from option/keyword string to object with completion.
Raises when ambiguously completable string is encountered.