This method is deprecated or moved on the latest stable version.
The last existing version (v1.2.6) is shown here.
of_caller(&block)
public
This method returns the binding of the method that called your method. It
will raise an Exception when you're not
inside a method.
It's used like this:
def inc_counter(amount=1)Binding.of_callerdo|binding|# Create a lambda that will increase the variable 'counter'# in the caller of this method when called.inc=eval("lambda { |arg| counter += arg }",binding)# We can refer to amount from inside this block safely.inc.call(amount)end# No other statements can go here. Put them inside the block.endcounter=02.times{inc_counter}counter# => 2
Binding.of_caller must be the last statement in the method. This means that
you will have to put everything you want to do after the call to
Binding.of_caller into the block of it. This should be no problem however,
because Ruby has closures. If you don't do this an Exception will be raised. Because of the way
that Binding.of_caller is implemented it has to be done this way.
# File activesupport/lib/active_support/binding_of_caller.rb, line 39
def Binding.of_caller(&block)
old_critical = Thread.critical
Thread.critical = true
count = 0
cc, result, error, extra_data = Continuation.create(nil, nil)
error.call if error
tracer = lambda do |*args|
type, context, extra_data = args[0], args[4], args
if type == "return"
count += 1
# First this method and then calling one will return --
# the trace event of the second event gets the context
# of the method which called the method that called this
# method.
if count == 2
# It would be nice if we could restore the trace_func
# that was set before we swapped in our own one, but
# this is impossible without overloading set_trace_func
# in current Ruby.
set_trace_func(nil)
cc.call(eval("binding", context), nil, extra_data)
end
elsif type == "line" then
nil
elsif type == "c-return" and extra_data[3] == :set_trace_func then
nil
else
set_trace_func(nil)
error_msg = "Binding.of_caller used in non-method context or " +
"trailing statements of method using it aren't in the block."
cc.call(nil, lambda { raise(ArgumentError, error_msg) }, nil)
end
end
unless result
set_trace_func(tracer)
return nil
else
Thread.critical = old_critical
case block.arity
when 1 then yield(result)
else yield(result, extra_data)
end
end
end