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"
 static VALUE
key_err_initialize(int argc, VALUE *argv, VALUE self)
{
    VALUE options;
    rb_call_super(rb_scan_args(argc, argv, "01:", NULL, &options), argv);
    if (!NIL_P(options)) {
        ID keywords[2];
        VALUE values[numberof(keywords)];
        int i;
        keywords[0] = id_receiver;
        keywords[1] = id_key;
        rb_get_kwargs(options, keywords, 0, numberof(values), values);
        for (i = 0; i < numberof(values); ++i) {
            if (values[i] != Qundef) {
                rb_ivar_set(self, keywords[i], values[i]);
            }
        }
    }
    return self;
} Construct a new KeyError exception with the given message, receiver and key.
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");
} Return the key caused this KeyError exception.
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");
} Return the receiver associated with this KeyError exception.
    Ruby Core © 1993–2020 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.