Returns the value of the given instance variable, or nil if the instance variable is not set. The @ part of the variable name should be included for regular instance variables. Throws a NameError exception if the supplied symbol is not valid as an instance variable name. String arguments are converted to symbols.
class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_get(:@a) #=> "cat" fred.instance_variable_get("@b") #=> 99
Sets the instance variable named by symbol to the given object. This may circumvent the encapsulation intended by the author of the class, so it should be used with care. The variable does not have to exist prior to this call. If the instance variable name is passed as a string, that string is converted to a symbol.
class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_set(:@a, 'dog') #=> "dog" fred.instance_variable_set(:@c, 'cat') #=> "cat" fred.inspect #=> "#<Fred:0x401b3da8 @a=\"dog\", @b=99, @c=\"cat\">"
Returns true if the given instance variable is defined in obj. String arguments are converted to symbols.
class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_defined?(:@a) #=> true fred.instance_variable_defined?("@b") #=> true fred.instance_variable_defined?("@c") #=> false
for compatibility
Returns true when OLE object has OLE method, otherwise returns false.
ie = WIN32OLE.new('InternetExplorer.Application') ie.ole_respond_to?("gohome") => true
Attempts to enter exclusive section. Returns false if lock fails.
For backward compatibility
Return all reachable objects from ‘obj’.
This method returns all reachable objects from ‘obj’.
If ‘obj’ has two or more references to the same object ‘x’, then returned array only includes one ‘x’ object.
If ‘obj’ is a non-markable (non-heap management) object such as true, false, nil, symbols and Fixnums (and Flonum) then it simply returns nil.
If ‘obj’ has references to an internal object, then it returns instances of ObjectSpace::InternalObjectWrapper class. This object contains a reference to an internal object and you can check the type of internal object with ‘type’ method.
If ‘obj’ is instance of ObjectSpace::InternalObjectWrapper class, then this method returns all reachable object from an internal object, which is pointed by ‘obj’.
With this method, you can find memory leaks.
This method is only expected to work with C Ruby.
Example:
ObjectSpace.reachable_objects_from(['a', 'b', 'c']) #=> [Array, 'a', 'b', 'c'] ObjectSpace.reachable_objects_from(['a', 'a', 'a']) #=> [Array, 'a', 'a', 'a'] # all 'a' strings have different object id ObjectSpace.reachable_objects_from([v = 'a', v, v]) #=> [Array, 'a'] ObjectSpace.reachable_objects_from(1) #=> nil # 1 is not markable (heap managed) object
Load the document contained in filename. Returns the yaml contained in filename as a Ruby object, or if the file is empty, it returns the specified fallback return value, which defaults to false.
NOTE: This method *should not* be used to parse untrusted documents, such as YAML documents that are supplied via user input. Instead, please use the safe_load_file method.
Finds the user’s config file
Default options for gem commands for Ruby packagers.
The options here should be structured as an array of string “gem” command names as keys and a string of the default options as values.
Example:
def self.operating_system_defaults
{
'install' => '--no-rdoc --no-ri --env-shebang',
'update' => '--no-rdoc --no-ri --env-shebang'
}
end
Shortcut for defining multiple delegator methods, but with no provision for using a different name. The following two code samples have the same effect:
def_delegators :@records, :size, :<<, :map def_delegator :@records, :size def_delegator :@records, :<< def_delegator :@records, :map
Define method as delegator instance method with an optional alias name ali. Method calls to ali will be delegated to accessor.method. accessor should be a method name, instance variable name, or constant name. Use the full path to the constant if providing the constant name. Returns the name of the method defined.
class MyQueue CONST = 1 extend Forwardable attr_reader :queue def initialize @queue = [] end def_delegator :@queue, :push, :mypush def_delegator 'MyQueue::CONST', :to_i end q = MyQueue.new q.mypush 42 q.queue #=> [42] q.push 23 #=> NoMethodError q.to_i #=> 1
Like URI.decode_www_form_component, except that '+' is preserved.
Returns a URL-encoded string derived from the given Enumerable enum.
The result is suitable for use as form data for an HTTP request whose Content-Type is 'application/x-www-form-urlencoded'.
The returned string consists of the elements of enum, each converted to one or more URL-encoded strings, and all joined with character '&'.
Simple examples:
URI.encode_www_form([['foo', 0], ['bar', 1], ['baz', 2]]) # => "foo=0&bar=1&baz=2" URI.encode_www_form({foo: 0, bar: 1, baz: 2}) # => "foo=0&bar=1&baz=2"
The returned string is formed using method URI.encode_www_form_component, which converts certain characters:
URI.encode_www_form('f#o': '/', 'b-r': '$', 'b z': '@') # => "f%23o=%2F&b-r=%24&b+z=%40"
When enum is Array-like, each element ele is converted to a field:
If ele is an array of two or more elements, the field is formed from its first two elements (and any additional elements are ignored):
name = URI.encode_www_form_component(ele[0], enc) value = URI.encode_www_form_component(ele[1], enc) "#{name}=#{value}"
Examples:
URI.encode_www_form([%w[foo bar], %w[baz bat bah]]) # => "foo=bar&baz=bat" URI.encode_www_form([['foo', 0], ['bar', :baz, 'bat']]) # => "foo=0&bar=baz"
If ele is an array of one element, the field is formed from ele[0]:
URI.encode_www_form_component(ele[0])
Example:
URI.encode_www_form([['foo'], [:bar], [0]]) # => "foo&bar&0"
Otherwise the field is formed from ele:
URI.encode_www_form_component(ele)
Example:
URI.encode_www_form(['foo', :bar, 0]) # => "foo&bar&0"
The elements of an Array-like enum may be mixture:
URI.encode_www_form([['foo', 0], ['bar', 1, 2], ['baz'], :bat]) # => "foo=0&bar=1&baz&bat"
When enum is Hash-like, each key/value pair is converted to one or more fields:
If value is Array-convertible, each element ele in value is paired with key to form a field:
name = URI.encode_www_form_component(key, enc) value = URI.encode_www_form_component(ele, enc) "#{name}=#{value}"
Example:
URI.encode_www_form({foo: [:bar, 1], baz: [:bat, :bam, 2]}) # => "foo=bar&foo=1&baz=bat&baz=bam&baz=2"
Otherwise, key and value are paired to form a field:
name = URI.encode_www_form_component(key, enc) value = URI.encode_www_form_component(value, enc) "#{name}=#{value}"
Example:
URI.encode_www_form({foo: 0, bar: 1, baz: 2}) # => "foo=0&bar=1&baz=2"
The elements of a Hash-like enum may be mixture:
URI.encode_www_form({foo: [0, 1], bar: 2}) # => "foo=0&foo=1&bar=2"