This handler will capture an event and record the event. Recorder
events are available vial Psych::Handlers::Recorder#events
.
For example:
recorder = Psych::Handlers::Recorder.new parser = Psych::Parser.new recorder parser.parse '--- foo' recorder.events # => [list of events] # Replay the events emitter = Psych::Emitter.new $stdout recorder.events.each do |m, args| emitter.send m, *args end
Represents a YAML
stream. This is the root node for any YAML
parse tree. This node must have one or more child nodes. The only valid child node for a Psych::Nodes::Stream
node is Psych::Nodes::Document
.
File-based session storage class.
Implements session storage as a flat file of ‘key=value’ values. This storage type only works directly with String
values; the user is responsible for converting other types to Strings when storing and from Strings when retrieving.
Dummy session storage class.
Implements session storage place holder. No actual storage will be done.
PStore-based session storage class.
This builds upon the top-level PStore
class provided by the library file pstore.rb. Session
data is marshalled and stored in a file. File
locking and transaction services are provided.
Used Internally. Wraps a Dependency object to also track which spec contained the Dependency.
A VendorSpecification
represents a gem that has been unpacked into a project and is being loaded through a gem dependencies file through the path:
option.
For detail, see the MSDN.
— HKEY_*
Predefined key ((*handle*)). These are Integer, not Win32::Registry.
— REG_*
Registry value type.
— KEY_*
Security access mask.
— KEY_OPTIONS_*
Key options.
If the key is created newly or opened existing key. See also Registry#disposition method.
Converts Ruby link flags into something cargo understands
Indicates a problem with the DNS
request.
IO
wrapper that allows writing a limited amount of data
Provides information about specifications and dependencies to the resolver, allowing the {Resolver} class to remain generic while still providing power and flexibility.
This module contains the methods that users of Gem::Resolver::Molinillo
must to implement, using knowledge of their own model classes.
Delegates
all {Gem::Resolver::Molinillo::ResolutionState} methods to a ‘#state` property.
Continuation
objects are generated by Kernel#callcc
, after having +require+d continuation. They hold a return address and execution context, allowing a nonlocal return to the end of the callcc
block from anywhere within a program. Continuations are somewhat analogous to a structured version of C’s setjmp/longjmp
(although they contain more state, so you might consider them closer to threads).
For instance:
require "continuation" arr = [ "Freddie", "Herbie", "Ron", "Max", "Ringo" ] callcc{|cc| $cc = cc} puts(message = arr.shift) $cc.call unless message =~ /Max/
produces:
Freddie Herbie Ron Max
Also you can call callcc in other methods:
require "continuation" def g arr = [ "Freddie", "Herbie", "Ron", "Max", "Ringo" ] cc = callcc { |cc| cc } puts arr.shift return cc, arr.size end def f c, size = g c.call(c) if size > 1 end f
This (somewhat contrived) example allows the inner loop to abandon processing early:
require "continuation" callcc {|cont| for i in 0..4 print "#{i}: " for j in i*5...(i+1)*5 cont.call() if j == 17 printf "%3d", j end end } puts
produces:
0: 0 1 2 3 4 1: 5 6 7 8 9 2: 10 11 12 13 14 3: 15 16
Raised to stop the iteration, in particular by Enumerator#next
. It is rescued by Kernel#loop
.
loop do puts "Hello" raise StopIteration puts "World" end puts "Done!"
produces:
Hello Done!
An OpenStruct
is a data structure, similar to a Hash
, that allows the definition of arbitrary attributes with their accompanying values. This is accomplished by using Ruby’s metaprogramming to define methods on the class itself.
require "ostruct" person = OpenStruct.new person.name = "John Smith" person.age = 70 person.name # => "John Smith" person.age # => 70 person.address # => nil
An OpenStruct
employs a Hash
internally to store the attributes and values and can even be initialized with one:
australia = OpenStruct.new(:country => "Australia", :capital => "Canberra") # => #<OpenStruct country="Australia", capital="Canberra">
Hash
keys with spaces or characters that could normally not be used for method calls (e.g. ()[]*
) will not be immediately available on the OpenStruct
object as a method for retrieval or assignment, but can still be reached through the Object#send
method or using [].
measurements = OpenStruct.new("length (in inches)" => 24) measurements[:"length (in inches)"] # => 24 measurements.send("length (in inches)") # => 24 message = OpenStruct.new(:queued? => true) message.queued? # => true message.send("queued?=", false) message.queued? # => false
Removing the presence of an attribute requires the execution of the delete_field
method as setting the property value to nil
will not remove the attribute.
first_pet = OpenStruct.new(:name => "Rowdy", :owner => "John Smith") second_pet = OpenStruct.new(:name => "Rowdy") first_pet.owner = nil first_pet # => #<OpenStruct name="Rowdy", owner=nil> first_pet == second_pet # => false first_pet.delete_field(:owner) first_pet # => #<OpenStruct name="Rowdy"> first_pet == second_pet # => true
Ractor
compatibility: A frozen OpenStruct
with shareable values is itself shareable.
An OpenStruct
utilizes Ruby’s method lookup structure to find and define the necessary methods for properties. This is accomplished through the methods method_missing and define_singleton_method.
This should be a consideration if there is a concern about the performance of the objects that are created, as there is much more overhead in the setting of these properties compared to using a Hash
or a Struct
. Creating an open struct from a small Hash
and accessing a few of the entries can be 200 times slower than accessing the hash directly.
This is a potential security issue; building OpenStruct
from untrusted user data (e.g. JSON
web request) may be susceptible to a “symbol denial of service” attack since the keys create methods and names of methods are never garbage collected.
This may also be the source of incompatibilities between Ruby versions:
o = OpenStruct.new o.then # => nil in Ruby < 2.6, enumerator for Ruby >= 2.6
Builtin methods may be overwritten this way, which may be a source of bugs or security issues:
o = OpenStruct.new o.methods # => [:to_h, :marshal_load, :marshal_dump, :each_pair, ... o.methods = [:foo, :bar] o.methods # => [:foo, :bar]
To help remedy clashes, OpenStruct
uses only protected/private methods ending with !
and defines aliases for builtin public methods by adding a !
:
o = OpenStruct.new(make: 'Bentley', class: :luxury) o.class # => :luxury o.class! # => OpenStruct
It is recommended (but not enforced) to not use fields ending in !
; Note that a subclass’ methods may not be overwritten, nor can OpenStruct’s own methods ending with !
.
For all these reasons, consider not using OpenStruct
at all.
Kanji Converter for Ruby.
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 install and update options for Gem::Commands
Helper methods for both Gem::Installer
and Gem::Uninstaller