Set
local variable named symbol
as obj
.
def foo a = 1 bind = binding bind.local_variable_set(:a, 2) # set existing local variable `a' bind.local_variable_set(:b, 3) # create new local variable `b' # `b' exists only in binding p bind.local_variable_get(:a) #=> 2 p bind.local_variable_get(:b) #=> 3 p a #=> 2 p b #=> NameError end
This method behaves similarly to the following code:
binding.eval("#{symbol} = #{obj}")
if obj
can be dumped in Ruby code.
Returns true
if a local variable symbol
exists.
def foo a = 1 binding.local_variable_defined?(:a) #=> true binding.local_variable_defined?(:b) #=> false end
This method is the short version of the following code:
binding.eval("defined?(#{symbol}) == 'local-variable'")
Task
description for the rerdoc task or its renamed description
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.
The Kernel#require
from before RubyGems was loaded.
Returns the last win32 Error
of the current executing Thread
or nil if none
Sets the last win32 Error
of the current executing Thread
to error
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.
Returns the class for the given object
.
class A def foo ObjectSpace::trace_object_allocations do obj = Object.new p "#{ObjectSpace::allocation_class_path(obj)}" end end end A.new.foo #=> "Class"
See ::trace_object_allocations
for more information and examples.
Returns the method identifier for the given object
.
class A include ObjectSpace def foo trace_object_allocations do obj = Object.new p "#{allocation_class_path(obj)}##{allocation_method_id(obj)}" end end end A.new.foo #=> "Class#new"
See ::trace_object_allocations
for more information and examples.
Return internal class of obj.
obj can be an instance of InternalObjectWrapper
.
Note that you should not use this method in your application.
Returns the terminal’s rows and columns.
See GNU Readline’s rl_get_screen_size function.
Raises NotImplementedError
if the using readline library does not support.
Specifies a character to be appended on completion. Nothing will be appended if an empty string (“”) or nil is specified.
For example:
require "readline" Readline.readline("> ", true) Readline.completion_append_character = " "
Result:
> Input "/var/li". > /var/li Press TAB key. > /var/lib Completes "b" and appends " ". So, you can continuously input "/usr". > /var/lib /usr
NOTE: Only one character can be specified. When “string” is specified, sets only “s” that is the first.
require "readline" Readline.completion_append_character = "string" p Readline.completion_append_character # => "s"
Raises NotImplementedError
if the using readline library does not support.
Returns a string containing a character to be appended on completion. The default is a space (“ ”).
Raises NotImplementedError
if the using readline library does not support.
Sets a list of quote characters which can cause a word break.
Raises NotImplementedError
if the using readline library does not support.
Gets a list of quote characters which can cause a word break.
Raises NotImplementedError
if the using readline library does not support.
Sets a list of characters that cause a filename to be quoted by the completer when they appear in a completed filename. The default is nil.
Raises NotImplementedError
if the using readline library does not support.
Gets a list of characters that cause a filename to be quoted by the completer when they appear in a completed filename.
Raises NotImplementedError
if the using readline library does not support.
Returns whether or not the struct of type type
contains member
. If it does not, or the struct type can’t be found, then false is returned. You may optionally specify additional headers
in which to look for the struct (in addition to the common header files).
If found, a macro is passed as a preprocessor constant to the compiler using the type name and the member name, in uppercase, prepended with HAVE_
.
For example, if have_struct_member('struct foo', 'bar')
returned true, then the HAVE_STRUCT_FOO_BAR
preprocessor macro would be passed to the compiler.
HAVE_ST_BAR
is also defined for backward compatibility.
Attempts to enter exclusive section. Returns false
if lock fails.
For backward compatibility
Quietly ensure the Gem directory dir
contains all the proper subdirectories. If we can’t create a directory due to a permission problem, then we will silently continue.
If mode
is given, missing directories are created with this mode.
World-writable directories will never be created.