Exception: KeyError

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, ::IndexError, ::StandardError, ::Exception
Instance Chain: self, ::IndexError, ::StandardError, ::Exception
Inherits:	IndexError ::Object Exception StandardError IndexError KeyError
Defined in:	error.c, error.c

Overview

Raised when the specified key is not found. It is a subclass of ::IndexError.

h = {"foo" => :bar}
h.fetch("foo") #=> :bar
h.fetch("baz") #=> KeyError: key not found: "baz"

Class Attribute Summary

::Exception - Inherited

.to_tty?

Returns true if exception messages will be sent to a tty.

Class Method Summary

::Exception - Inherited

.exception	With no argument, or if the argument is the same as the receiver, return the receiver.
.new	Construct a new ::Exception object, optionally passing in a message.

Instance Method Summary

#key ⇒ Object

Return the key caused this KeyError exception.
#receiver ⇒ Object

Return the receiver associated with this KeyError exception.

::Exception - Inherited

#==	Equality—If obj is not an ::Exception, returns `false`.
#backtrace	Returns any backtrace associated with the exception.
#backtrace_locations	Returns any backtrace associated with the exception.
#cause	Returns the previous exception ($!) at the time this exception was raised.
#exception	With no argument, or if the argument is the same as the receiver, return the receiver.
#full_message	Returns formatted string of exception.
#inspect	Return this exception's class name and message.
#message	Returns the result of invoking `exception.to_s`.
#set_backtrace	Sets the backtrace information associated with `exc`.
#to_s	Returns exception's message (or the name of the exception if no message is set).

Constructor Details

This class inherits a constructor from Exception

Instance Method Details

#key ⇒ Object

Return the key caused this KeyError exception.

[ GitHub ]

# File 'error.c', line 1713


static VALUE
key_err_key(VALUE self)
{
    VALUE key;

    key = rb_ivar_lookup(self, id_key, Qundef);
    if (key != Qundef) return key;
    rb_raise(rb_eArgError, "no key is available");
}

#receiver ⇒ Object

Return the receiver associated with this KeyError exception.

[ GitHub ]

# File 'error.c', line 1696


static VALUE
key_err_receiver(VALUE self)
{
    VALUE recv;

    recv = rb_ivar_lookup(self, id_receiver, Qundef);
    if (recv != Qundef) return recv;
    rb_raise(rb_eArgError, "no receiver is available");
}