Attempts to obtain the lock and returns immediately. Returns true if the lock was granted.
Return class or module of the method being called.
class C; def foo; end; end trace = TracePoint.new(:call) do |tp| p tp.defined_class #=> C end.enable do C.new.foo end
If method is defined by a module, then that module is returned.
module M; def foo; end; end class C; include M; end; trace = TracePoint.new(:call) do |tp| p tp.defined_class #=> M end.enable do C.new.foo end
Note: defined_class returns singleton class.
6th block parameter of Kernel#set_trace_func passes original class of attached by singleton class.
This is a difference between Kernel#set_trace_func and TracePoint.
class C; def self.foo; end; end trace = TracePoint.new(:call) do |tp| p tp.defined_class #=> #<Class:C> end.enable do C.foo end
Returns an array of the names of global variables.
global_variables.grep /std/ #=> [:$stdin, :$stdout, :$stderr]
Controls tracing of assignments to global variables. The parameter symbol identifies the variable (as either a string name or a symbol identifier). cmd (which may be a string or a Proc object) or block is executed whenever the variable is assigned. The block or Proc object receives the variable’s new value as a parameter. Also see Kernel::untrace_var.
trace_var :$_, proc {|v| puts "$_ is now '#{v}'" } $_ = "hello" $_ = ' there'
produces:
$_ is now 'hello' $_ is now ' there'
Removes tracing for the specified command on the given global variable and returns nil. If no command is specified, removes all tracing for that variable and returns an array containing the commands actually removed.
Returns a pretty printed object as a string.
In order to use this method you must first require the PP module:
require 'pp'
See the PP module for more information.
Returns the names of the current local variables.
fred = 1 for i in 1..10 # ... end local_variables #=> [:fred, :i]
Returns an array containing all elements of enum for which the given block returns a true value.
If no block is given, an Enumerator is returned instead.
(1..10).find_all { |i| i % 3 == 0 } #=> [3, 6, 9] [1,2,3,4,5].select { |num| num.even? } #=> [2, 4]
See also Enumerable#reject.
Returns the object in enum that gives the minimum value from the given block.
If no block is given, an enumerator is returned instead.
a = %w(albatross dog horse) a.min_by { |x| x.length } #=> "dog"
If the n argument is given, minimum n elements are returned as an array. These n elements are sorted by the value from the given block.
a = %w[albatross dog horse] p a.min_by(2) {|x| x.length } #=> ["dog", "horse"]
Returns a two element array containing the objects in enum that correspond to the minimum and maximum values respectively from the given block.
If no block is given, an enumerator is returned instead.
a = %w(albatross dog horse) a.minmax_by { |x| x.length } #=> ["dog", "albatross"]
Calls block once for each element in self, passing that element as a parameter, converting multiple values from yield to an array.
If no block is given, an enumerator is returned instead.
class Foo include Enumerable def each yield 1 yield 1, 2 yield end end Foo.new.each_entry{ |o| p o }
produces:
1 [1, 2] nil
Returns the last Error of the current executing Thread or nil if none
Sets the last Error of the current executing Thread to error
Generate a JSON document from the Ruby data structure obj and return it. This method disables the checks for circles in Ruby objects.
WARNING: Be careful not to pass any Ruby data structures with circles as obj argument because this will cause JSON to go into an infinite loop.
Returns the original line from source for from the given object.
See ::trace_object_allocations for more information and examples.
Returns the full line that is being edited. This is useful from within the complete_proc for determining the context of the completion request.
The length of Readline.line_buffer and GNU Readline’s rl_end are same.
Raises NotImplementedError if the using readline library does not support.
Clear the current input line.
Insert text into the line at the current cursor position.
See GNU Readline’s rl_insert_text function.
Raises NotImplementedError if the using readline library does not support.
Combine two Adler-32 check values in to one. alder1 is the first Adler-32 value, adler2 is the second Adler-32 value. len2 is the length of the string used to generate adler2.
Combine two CRC-32 check values in to one. crc1 is the first CRC-32 value, crc2 is the second CRC-32 value. len2 is the length of the string used to generate crc2.
Returns true if the named file is writable by the real user and group id of this process. See access(3)
If file_name is writable by others, returns an integer representing the file permission bits of file_name. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).
file_name can be an IO object.
File.world_writable?("/tmp") #=> 511 m = File.world_writable?("/tmp") sprintf("%o", m) #=> "777"
Start a dRuby server locally.
The new dRuby server will become the primary server, even if another server is currently the primary server.
uri is the URI for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.
front is the server’s front object. This may be nil.
config is the configuration for the new server. This may be nil.
See DRbServer::new.
Start a dRuby server locally.
The new dRuby server will become the primary server, even if another server is currently the primary server.
uri is the URI for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.
front is the server’s front object. This may be nil.
config is the configuration for the new server. This may be nil.
See DRbServer::new.
Stop the local dRuby server.
This operates on the primary server. If there is no primary server currently running, it is a noop.