Calls the given block with each successive grapheme cluster from self
(see Unicode Grapheme Cluster Boundaries); returns self
:
s = "\u0061\u0308-pqr-\u0062\u0308-xyz-\u0063\u0308" # => "ä-pqr-b̈-xyz-c̈" s.each_grapheme_cluster {|gc| print gc, ' ' }
Output:
ä - p q r - b̈ - x y z - c̈
Returns an enumerator if no block is given.
Same as Enumerator#with_index(0)
, i.e. there is no starting offset.
If no block is given, a new Enumerator
is returned that includes the index.
Iterates the given block for each element with an arbitrary object, obj
, and returns obj
If no block is given, returns a new Enumerator
.
to_three = Enumerator.new do |y| 3.times do |x| y << x end end to_three_with_string = to_three.with_object("foo") to_three_with_string.each do |x,string| puts "#{string}: #{x}" end # => foo: 0 # => foo: 1 # => foo: 2
Returns the Ruby source filename and line number containing the definition of the constant specified. If the named constant is not found, nil
is returned. If the constant is found, but its source location can not be extracted (constant is defined in C code), empty array is returned.
inherit specifies whether to lookup in mod.ancestors
(true
by default).
# test.rb: class A # line 1 C1 = 1 C2 = 2 end module M # line 6 C3 = 3 end class B < A # line 10 include M C4 = 4 end class A # continuation of A definition C2 = 8 # constant redefinition; warned yet allowed end p B.const_source_location('C4') # => ["test.rb", 12] p B.const_source_location('C3') # => ["test.rb", 7] p B.const_source_location('C1') # => ["test.rb", 2] p B.const_source_location('C3', false) # => nil -- don't lookup in ancestors p A.const_source_location('C2') # => ["test.rb", 16] -- actual (last) definition place p Object.const_source_location('B') # => ["test.rb", 10] -- top-level constant could be looked through Object p Object.const_source_location('A') # => ["test.rb", 1] -- class reopening is NOT considered new definition p B.const_source_location('A') # => ["test.rb", 1] -- because Object is in ancestors p M.const_source_location('A') # => ["test.rb", 1] -- Object is not ancestor, but additionally checked for modules p Object.const_source_location('A::C1') # => ["test.rb", 2] -- nesting is supported p Object.const_source_location('String') # => [] -- constant is defined in C code
Makes the set compare its elements by their identity and returns self. This method may not be supported by all subclasses of Set
.
Returns true if the set will compare its elements by their identity. Also see Set#compare_by_identity
.
Packs port and host as an AF_INET/AF_INET6 sockaddr string.
Socket.sockaddr_in(80, "127.0.0.1") #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" Socket.sockaddr_in(80, "::1") #=> "\n\x00\x00P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00"
Unpacks sockaddr into port and ip_address.
sockaddr should be a string or an addrinfo for AF_INET/AF_INET6.
sockaddr = Socket.sockaddr_in(80, "127.0.0.1") p sockaddr #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" p Socket.unpack_sockaddr_in(sockaddr) #=> [80, "127.0.0.1"]
Packs path as an AF_UNIX
sockaddr string.
Socket.sockaddr_un("/tmp/sock") #=> "\x01\x00/tmp/sock\x00\x00..."
Unpacks sockaddr into path.
sockaddr should be a string or an addrinfo for AF_UNIX
.
sockaddr = Socket.sockaddr_un("/tmp/sock") p Socket.unpack_sockaddr_un(sockaddr) #=> "/tmp/sock"
Sets self
to consider only identity in comparing keys; two keys are considered the same only if they are the same object; returns self
.
By default, these two object are considered to be the same key, so s1
will overwrite s0
:
s0 = 'x' s1 = 'x' h = {} h.compare_by_identity? # => false h[s0] = 0 h[s1] = 1 h # => {"x"=>1}
After calling #compare_by_identity, the keys are considered to be different, and therefore do not overwrite each other:
h = {} h.compare_by_identity # => {} h.compare_by_identity? # => true h[s0] = 0 h[s1] = 1 h # => {"x"=>0, "x"=>1}
Returns true
if compare_by_identity
has been called, false
otherwise.
Render a template on a new toplevel binding with local variables specified by a Hash
object.
Returns the value of a thread local variable that has been set. Note that these are different than fiber local values. For fiber local values, please see Thread#[]
and Thread#[]=
.
Thread
local values are carried along with threads, and do not respect fibers. For example:
Thread.new { Thread.current.thread_variable_set("foo", "bar") # set a thread local Thread.current["foo"] = "bar" # set a fiber local Fiber.new { Fiber.yield [ Thread.current.thread_variable_get("foo"), # get the thread local Thread.current["foo"], # get the fiber local ] }.resume }.join.value # => ['bar', nil]
The value “bar” is returned for the thread local, where nil is returned for the fiber local. The fiber is executed in the same thread, so the thread local values are available.
Sets a thread local with key
to value
. Note that these are local to threads, and not to fibers. Please see Thread#thread_variable_get
and Thread#[]
for more information.
Yields each frame of the current execution stack as a backtrace location object.
Invoke self.each
with *args
. With a block given, the block receives each element and its index; returns self
:
h = {} (1..4).each_with_index {|element, i| h[element] = i } # => 1..4 h # => {1=>0, 2=>1, 3=>2, 4=>3} h = {} %w[a b c d].each_with_index {|element, i| h[element] = i } # => ["a", "b", "c", "d"] h # => {"a"=>0, "b"=>1, "c"=>2, "d"=>3} a = [] h = {foo: 0, bar: 1, baz: 2} h.each_with_index {|element, i| a.push([i, element]) } # => {:foo=>0, :bar=>1, :baz=>2} a # => [[0, [:foo, 0]], [1, [:bar, 1]], [2, [:baz, 2]]]
With no block given, returns an Enumerator
.
Calls the block once for each element, passing both the element and the given object:
(1..4).each_with_object([]) {|i, a| a.push(i**2) } # => [1, 4, 9, 16] {foo: 0, bar: 1, baz: 2}.each_with_object({}) {|(k, v), h| h[v] = k } # => {0=>:foo, 1=>:bar, 2=>:baz}
With no block given, returns an Enumerator
.
Starts tracing object allocations from the ObjectSpace
extension module.
For example:
require 'objspace' class C include ObjectSpace def foo trace_object_allocations do obj = Object.new p "#{allocation_sourcefile(obj)}:#{allocation_sourceline(obj)}" end end end C.new.foo #=> "objtrace.rb:8"
This example has included the ObjectSpace
module to make it easier to read, but you can also use the ::trace_object_allocations
notation (recommended).
Note that this feature introduces a huge performance decrease and huge memory consumption.
Return consuming memory size of all living objects in bytes.
If klass
(should be Class
object) is given, return the total memory size of instances of the given class.
Note that the returned size is incomplete. You need to deal with this information as only a HINT. Especially, the size of T_DATA
may not be correct.
Note that this method does NOT return total malloc’ed memory size.
This method can be defined by the following Ruby code:
def memsize_of_all klass = false total = 0 ObjectSpace.each_object{|e| total += ObjectSpace.memsize_of(e) if klass == false || e.kind_of?(klass) } total end
This method is only expected to work with C Ruby.
Counts objects for each T_DATA
type.
This method is only for MRI developers interested in performance and memory usage of Ruby programs.
It returns a hash as:
{RubyVM::InstructionSequence=>504, :parser=>5, :barrier=>6, :mutex=>6, Proc=>60, RubyVM::Env=>57, Mutex=>1, Encoding=>99, ThreadGroup=>1, Binding=>1, Thread=>1, RubyVM=>1, :iseq=>1, Random=>1, ARGF.class=>1, Data=>1, :autoload=>3, Time=>2} # T_DATA objects existing at startup on r32276.
If the optional argument, result_hash, is given, it is overwritten and returned. This is intended to avoid probe effect.
The contents of the returned hash is implementation specific and may change in the future.
In this version, keys are Class
object or Symbol
object.
If object is kind of normal (accessible) object, the key is Class
object. If object is not a kind of normal (internal) object, the key is symbol name, registered by rb_data_type_struct.
This method is only expected to work with C Ruby.