/*
* call-seq:
* obj.instance_variable_get(symbol) -> obj
*
* Returns the value of the given instance variable, or nil if the
* instance variable is not set. The <code>@</code> part of the
* variable name should be included for regular instance
* variables. Throws a <code>NameError</code> exception if the
* supplied symbol is not valid as an instance variable name.
*
* class Fred
* def initialize(p1, p2)
* @a, @b = p1, p2
* end
* end
* fred = Fred.new('cat', 99)
* fred.instance_variable_get(:@a) #=> "cat"
* fred.instance_variable_get("@b") #=> 99
*/
mrb_value
mrb_obj_ivar_get(mrb_state *mrb, mrb_value self)
{
mrb_sym id;
mrb_get_args(mrb, "n", &id);
check_iv_name(mrb, id);
return mrb_iv_get(mrb, self, id);
}
/*
* call-seq:
* obj.instance_variable_set(symbol, obj) -> obj
*
* Sets the instance variable names by <i>symbol</i> to
* <i>object</i>, thereby frustrating the efforts of the class's
* author to attempt to provide proper encapsulation. The variable
* did not have to exist prior to this call.
*
* class Fred
* def initialize(p1, p2)
* @a, @b = p1, p2
* end
* end
* fred = Fred.new('cat', 99)
* fred.instance_variable_set(:@a, 'dog') #=> "dog"
* fred.instance_variable_set(:@c, 'cat') #=> "cat"
* fred.inspect #=> "#<Fred:0x401b3da8 @a=\"dog\", @b=99, @c=\"cat\">"
*/
mrb_value
mrb_obj_ivar_set(mrb_state *mrb, mrb_value self)
{
mrb_sym id;
mrb_value val;
mrb_get_args(mrb, "no", &id, &val);
check_iv_name(mrb, id);
mrb_iv_set(mrb, self, id, val);
return val;
}
/*
* call-seq:
* obj.instance_variable_defined?(symbol) -> true or false
*
* Returns <code>true</code> if the given instance variable is
* defined in <i>obj</i>.
*
* class Fred
* def initialize(p1, p2)
* @a, @b = p1, p2
* end
* end
* fred = Fred.new('cat', 99)
* fred.instance_variable_defined?(:@a) #=> true
* fred.instance_variable_defined?("@b") #=> true
* fred.instance_variable_defined?("@c") #=> false
*/
mrb_value
mrb_obj_ivar_defined(mrb_state *mrb, mrb_value self)
{
mrb_sym mid;
mrb_get_args(mrb, "n", &mid);
check_iv_name(mrb, mid);
if (mrb_obj_iv_defined(mrb, mrb_obj_ptr(self), mid))
return mrb_true_value();
return mrb_false_value();
}
/*
* call-seq:
* obj.instance_variable_defined?(symbol) -> true or false
*
* Returns <code>true</code> if the given instance variable is
* defined in <i>obj</i>.
*
* class Fred
* def initialize(p1, p2)
* @a, @b = p1, p2
* end
* end
* fred = Fred.new('cat', 99)
* fred.instance_variable_defined?(:@a) #=> true
* fred.instance_variable_defined?("@b") #=> true
* fred.instance_variable_defined?("@c") #=> false
*/
mrb_value
mrb_obj_ivar_defined(mrb_state *mrb, mrb_value self)
{
mrb_sym mid;
mrb_bool defined_p;
mrb_get_args(mrb, "n", &mid);
check_iv_name(mrb, mid);
defined_p = mrb_obj_iv_defined(mrb, mrb_obj_ptr(self), mid);
return mrb_bool_value(defined_p);
}
/*
* call-seq:
* obj.remove_instance_variable(symbol) -> obj
*
* Removes the named instance variable from <i>obj</i>, returning that
* variable's value.
*
* class Dummy
* attr_reader :var
* def initialize
* @var = 99
* end
* def remove
* remove_instance_variable(:@var)
* end
* end
* d = Dummy.new
* d.var #=> 99
* d.remove #=> 99
* d.var #=> nil
*/
mrb_value
mrb_obj_remove_instance_variable(mrb_state *mrb, mrb_value self)
{
mrb_sym sym;
mrb_value val;
mrb_get_args(mrb, "n", &sym);
check_iv_name(mrb, sym);
val = mrb_iv_remove(mrb, self, sym);
if (mrb_undef_p(val)) {
mrb_name_error(mrb, sym, "instance variable %S not defined", mrb_sym2str(mrb, sym));
}
return val;
}
static mrb_sym
get_valid_iv_sym(mrb_state *mrb, mrb_value iv_name)
{
mrb_sym iv_name_id;
mrb_assert(mrb_symbol_p(iv_name) || mrb_string_p(iv_name));
if (mrb_string_p(iv_name)) {
iv_name_id = mrb_intern_cstr(mrb, RSTRING_PTR(iv_name));
valid_iv_name(mrb, iv_name_id, RSTRING_PTR(iv_name), RSTRING_LEN(iv_name));
}
else {
iv_name_id = mrb_symbol(iv_name);
check_iv_name(mrb, iv_name_id);
}
return iv_name_id;
}