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.
Handle BasicObject
instances
Returns the value of the local variable symbol
.
def foo a = 1 binding.local_variable_get(:a) #=> 1 binding.local_variable_get(:b) #=> NameError end
This method is the short version of the following code:
binding.eval("#{symbol}")
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'")
Raises PStore::Error
if the calling code is not in a PStore#transaction
or if the code is in a read-only PStore#transaction
.
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.
Establishes proc on thr as the handler for tracing, or disables tracing if the parameter is nil
.
Adds proc as a handler for tracing.
Establishes proc as the handler for tracing, or disables tracing if the parameter is nil
.
Note: this method is obsolete, please use TracePoint
instead.
proc takes up to six parameters:
an event name string
a filename string
a line number
a method name symbol, or nil
a binding, or nil
the class, module, or nil
proc is invoked whenever an event occurs.
Events are:
"c-call"
call a C-language routine
"c-return"
return from a C-language routine
"call"
call a Ruby method
"class"
start a class or module definition
"end"
finish a class or module definition
"line"
execute code on a new line
"raise"
raise an exception
"return"
return from a Ruby method
Tracing is disabled within the context of proc.
class Test def test a = 1 b = 2 end end set_trace_func proc { |event, file, line, id, binding, class_or_module| printf "%8s %s:%-2d %16p %14p\n", event, file, line, id, class_or_module } t = Test.new t.test
Produces:
c-return prog.rb:8 :set_trace_func Kernel line prog.rb:11 nil nil c-call prog.rb:11 :new Class c-call prog.rb:11 :initialize BasicObject c-return prog.rb:11 :initialize BasicObject c-return prog.rb:11 :new Class line prog.rb:12 nil nil call prog.rb:2 :test Test line prog.rb:3 :test Test line prog.rb:4 :test Test return prog.rb:5 :test Test
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.
Clear default gem related variables. It is for test
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
Mirror the Prism.parse_file_comments
API by using the serialization API. This uses native strings instead of Ruby strings because it allows us to use mmap when it is available.
Mirror the Prism.parse_lex_file
API by using the serialization API.
Mirror the Prism.parse_file_success?
API by using the serialization API.
Mirror the Prism.parse_file_failure?
API by using the serialization API.