Returns true if the version is supported
Writes pemmable
, which must respond to to_pem
to path
with the given permissions
. If passed cipher
and passphrase
those arguments will be passed to to_pem
.
Displays an alert statement
. Asks a question
if given.
Escapes 8 bit characters in str
Switch the effective and real user IDs of the current process. If a block is given, the user IDs will be switched back after the block is executed. Returns the new effective user ID if called without a block, and the return value of the block if one is given.
Switch the effective and real group IDs of the current process. If a block is given, the group IDs will be switched back after the block is executed. Returns the new effective group ID if called without a block, and the return value of the block if one is given.
(see Gem::Resolver::Molinillo::ResolutionState#activated)
Attempts to activate the current {#possibility} (given that it has already been activated) @return [void]
Returns self
.
Sorts self
in place using a set of keys generated by mapping the values in self
through the given block.
The result is not guaranteed to be stable. When two keys are equal, the order of the corresponding elements is unpredictable.
If no block is given, an Enumerator
is returned instead.
See also Enumerable#sort_by
.
By using binary search, finds an index of a value from this array which meets the given condition in O(log n) where n is the size of the array.
It supports two modes, depending on the nature of the block and they are exactly the same as in the case of bsearch
method with the only difference being that this method returns the index of the element instead of the element itself. For more details consult the documentation for bsearch
.
Returns the singleton class of obj. This method creates a new singleton class if obj does not have one.
If obj is nil
, true
, or false
, it returns NilClass
, TrueClass
, or FalseClass
, respectively. If obj is an Integer
, a Float
or a Symbol
, it raises a TypeError
.
Object.new.singleton_class #=> #<Class:#<Object:0xb7ce1e24>> String.singleton_class #=> #<Class:String> nil.singleton_class #=> NilClass
Returns an array of the names of singleton methods for obj. If the optional all parameter is true, the list will include methods in modules included in obj. Only public and protected singleton methods are returned.
module Other def three() end end class Single def Single.four() end end a = Single.new def a.one() end class << a include Other def two() end end Single.singleton_methods #=> [:four] a.singleton_methods(false) #=> [:two, :one] a.singleton_methods #=> [:two, :one, :three]
Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.
class Fred attr_accessor :a1 def initialize @iv = 3 end end Fred.new.instance_variables #=> [:@iv]
Similar to method, searches singleton method only.
class Demo def initialize(n) @iv = n end def hello() "Hello, @iv = #{@iv}" end end k = Demo.new(99) def k.hi "Hi, @iv = #{@iv}" end m = k.singleton_method(:hi) m.call #=> "Hi, @iv = 99" m = k.singleton_method(:hello) #=> NameError
Returns true
if obj responds to the given method. Private and protected methods are included in the search only if the optional second parameter evaluates to true
.
If the method is not implemented, as Process.fork
on Windows, File.lchmod
on GNU/Linux, etc., false is returned.
If the method is not defined, respond_to_missing?
method is called and the result is returned.
When the method name parameter is given as a string, the string is converted to a symbol.
Returns the number of bits of the value of int.
“the number of bits” means that the bit position of the highest bit which is different to the sign bit. (The bit position of the bit 2**n is n+1.) If there is no such bit (zero or minus one), zero is returned.
I.e. This method returns ceil(log2(int < 0 ? -int : int+1)).
(-2**10000-1).bit_length #=> 10001 (-2**10000).bit_length #=> 10000 (-2**10000+1).bit_length #=> 10000 (-2**1000-1).bit_length #=> 1001 (-2**1000).bit_length #=> 1000 (-2**1000+1).bit_length #=> 1000 (-2**12-1).bit_length #=> 13 (-2**12).bit_length #=> 12 (-2**12+1).bit_length #=> 12 -0x101.bit_length #=> 9 -0x100.bit_length #=> 8 -0xff.bit_length #=> 8 -2.bit_length #=> 1 -1.bit_length #=> 0 0.bit_length #=> 0 1.bit_length #=> 1 0xff.bit_length #=> 8 0x100.bit_length #=> 9 (2**12-1).bit_length #=> 12 (2**12).bit_length #=> 13 (2**12+1).bit_length #=> 13 (2**1000-1).bit_length #=> 1000 (2**1000).bit_length #=> 1001 (2**1000+1).bit_length #=> 1001 (2**10000-1).bit_length #=> 10000 (2**10000).bit_length #=> 10001 (2**10000+1).bit_length #=> 10001
This method can be used to detect overflow in Array#pack
as follows.
if n.bit_length < 32 [n].pack("l") # no overflow else raise "overflow" end
Returns a hash, that will be turned into a JSON
object and represent this object.