Results for: "String# "

Returns range or nil

Called for dup & clone.

Private. Use Matrix#determinant

Returns the determinant of the matrix, using Bareiss’ multistep integer-preserving gaussian elimination. It has the same computational cost order O(n^3) as standard Gaussian elimination. Intermediate results are fraction free and of lower complexity. A matrix of Integers will have thus intermediate results that are also Integers, with smaller bignums (if any), while a matrix of Float will usually have intermediate results with better precision.

Called for dup & clone.

Returns the inner product of this vector with the other.

Vector[4,7].inner_product Vector[10,1]  => 47

Returns an angle with another vector. Result is within the [0..Math::PI].

Vector[1,0].angle_with(Vector[0,1])
# => Math::PI / 2

Returns the portion of the original string after the current match. Equivalent to the special variable $'.

m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie")
m.post_match   #=> ": The Movie"

Returns the factorization of value.

Parameters

value

An arbitrary integer.

generator

Optional. A pseudo-prime generator. generator.succ must return the next pseudo-prime number in the ascending order. It must generate all prime numbers, but may also generate non prime numbers too.

Exceptions

ZeroDivisionError

when value is zero.

Example

For an arbitrary integer:

n = p_1**e_1 * p_2**e_2 * .... * p_n**e_n,

prime_division(n) returns:

[[p_1, e_1], [p_2, e_2], ...., [p_n, e_n]].

Prime.prime_division(12) #=> [[2,2], [3,1]]

List of options that will be supplied to RDoc

Dup internal hash.

Clone internal hash.

Sets the system path (the Shell instance’s PATH environment variable).

path should be an array of directory name strings.

Specifies the threads that this object will wait for, but does not actually wait.

Specifies the threads that this object will wait for, but does not actually wait.

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

Compiled source code (String) on *eval methods on the :script_compiled event. If loaded from a file, it will return nil.

Changes asynchronous interrupt timing.

interrupt means asynchronous event and corresponding procedure by Thread#raise, Thread#kill, signal trap (not supported yet) and main thread termination (if main thread terminates, then all other thread will be killed).

The given hash has pairs like ExceptionClass => :TimingSymbol. Where the ExceptionClass is the interrupt handled by the given block. The TimingSymbol can be one of the following symbols:

:immediate

Invoke interrupts immediately.

:on_blocking

Invoke interrupts while BlockingOperation.

:never

Never invoke all interrupts.

BlockingOperation means that the operation will block the calling thread, such as read and write. On CRuby implementation, BlockingOperation is any operation executed without GVL.

Masked asynchronous interrupts are delayed until they are enabled. This method is similar to sigprocmask(3).

NOTE

Asynchronous interrupts are difficult to use.

If you need to communicate between threads, please consider to use another way such as Queue.

Or use them with deep understanding about this method.

Usage

In this example, we can guard from Thread#raise exceptions.

Using the :never TimingSymbol the RuntimeError exception will always be ignored in the first block of the main thread. In the second ::handle_interrupt block we can purposefully handle RuntimeError exceptions.

th = Thread.new do
  Thread.handle_interrupt(RuntimeError => :never) {
    begin
      # You can write resource allocation code safely.
      Thread.handle_interrupt(RuntimeError => :immediate) {
        # ...
      }
    ensure
      # You can write resource deallocation code safely.
    end
  }
end
Thread.pass
# ...
th.raise "stop"

While we are ignoring the RuntimeError exception, it’s safe to write our resource allocation code. Then, the ensure block is where we can safely deallocate your resources.

Guarding from Timeout::Error

In the next example, we will guard from the Timeout::Error exception. This will help prevent from leaking resources when Timeout::Error exceptions occur during normal ensure clause. For this example we use the help of the standard library Timeout, from lib/timeout.rb

require 'timeout'
Thread.handle_interrupt(Timeout::Error => :never) {
  timeout(10){
    # Timeout::Error doesn't occur here
    Thread.handle_interrupt(Timeout::Error => :on_blocking) {
      # possible to be killed by Timeout::Error
      # while blocking operation
    }
    # Timeout::Error doesn't occur here
  }
}

In the first part of the timeout block, we can rely on Timeout::Error being ignored. Then in the Timeout::Error => :on_blocking block, any operation that will block the calling thread is susceptible to a Timeout::Error exception being raised.

Stack control settings

It’s possible to stack multiple levels of ::handle_interrupt blocks in order to control more than one ExceptionClass and TimingSymbol at a time.

Thread.handle_interrupt(FooError => :never) {
  Thread.handle_interrupt(BarError => :never) {
     # FooError and BarError are prohibited.
  }
}

Inheritance with ExceptionClass

All exceptions inherited from the ExceptionClass parameter will be considered.

Thread.handle_interrupt(Exception => :never) {
  # all exceptions inherited from Exception are prohibited.
}