Kernel Module

These public methods are in the Kernel module, the module that is included in the Object class, the base class of Ruby. This documentation is adapted and abbreviated from, where you can find code examples and longer explanations:


Returns arg as an Array.


Returns arg converted to a float.


Converts arg to a Fixnum or Bignum.


Converts arg to a String by calling its to_s method.


Alias for URI.parse.


Returns the standard output of running cmd in a subshell.

abort [or] Kernel::abort [or] Process::abort

Terminate execution immediately, effectively by calling Kernel.exit(1).

at_exit { block }

Converts block to a Proc object (and therefore binds it at the point of call) and registers it for execution when the program exits.

autoload(module, filename)

Registers filename to be loaded (using Kernel::require) the first time that module—which may be a String or a symbol—is accessed.


Returns a Binding object, describing the variable and method bindings at the point of call.

block_given? [or] iterator?

Returns true if yield would execute a block in the current context. The iterator? form is mildly deprecated.

callcc { |cont| block }

Generates a continuation object, which it passes to the associated block.


Returns the current execution stack—an array containing strings in the form file:line or file:line: in method. The optional start parameter determines the number of initial ...

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