Ruby/Справочник/Exception

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Класс Exception[править]

Descendents of class Exception are used to communicate between raise methods and rescue statements in begin/end blocks. Exception objects carry information about the exception---its type (the exception's class name), an optional descriptive string, and optional traceback information. Programs may subclass Exception to add additional information.


Add file-blaming to exceptions


Методы класса

exception, new, yaml_new

Методы объекта

backtrace, exception, inspect, message, set_backtrace, to_str, to_s, to_yaml

Exception::exception[править]


 exc.exception(string) -> an_exception or exc

With no argument, or if the argument is the same as the receiver, return the receiver. Otherwise, create a new exception object of the same class as the receiver, but with a message equal to string.to_str.

Exception::new[править]


 Exception.new(msg = nil)   =>  exception

Construct a new Exception object, optionally passing in a message.


Exception#backtrace[править]


 exception.backtrace    => array

Returns any backtrace associated with the exception. The backtrace is an array of strings, each containing either ``filename:lineNo: in `method' or ``filename:lineNo.

  def a
    raise "boom"
  end
  def b
    a()
  end
  begin
    b()
  rescue => detail
    print detail.backtrace.join("\n")
  end

produces:

  prog.rb:2:in `a'
  prog.rb:6:in `b'
  prog.rb:10

Exception#exception[править]


 exc.exception(string) -> an_exception or exc

With no argument, or if the argument is the same as the receiver, return the receiver. Otherwise, create a new exception object of the same class as the receiver, but with a message equal to string.to_str.

Exception#inspect[править]


 exception.inspect   => string

Return this exception's class name an message

Exception#message[править]


 exception.message   =>  string
 exception.to_str    =>  string

Returns the result of invoking exception.to_s. Normally this returns the exception's message or name. By supplying a to_str method, exceptions are agreeing to be used where Strings are expected.

Exception#set_backtrace[править]


 exc.set_backtrace(array)   =>  array

Sets the backtrace information associated with exc. The argument must be an array of String objects in the format described in Exception#backtrace.

Exception#to_s[править]


 exception.to_s   =>  string

Returns exception's message (or the name of the exception if no message is set).

Exception#to_str[править]


 exception.message   =>  string
 exception.to_str    =>  string

Returns the result of invoking exception.to_s. Normally this returns the exception's message or name. By supplying a to_str method, exceptions are agreeing to be used where Strings are expected.