BasicObject
Object is the parent class of all classes in Ruby. Its methods are therefore available to all objects unless explicitly overridden.
Object mixes in the Kernel module, making the built-in kernel functions globally accessible. Although the instance methods of Object are defined by the Kernel module, we have chosen to document them here for clarity.
In the descriptions of Object’s methods, the parameter symbol refers to a symbol, which is either a quoted string or a Symbol (such as :name).
constants to hold original stdin/stdout/stderr
obsolete constants
Equality—At the Object level, == returns true only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
Unlike ==, the equal? method should never be overridden by subclasses: it is used to determine object identity (that is, a.equal?(b) iff a is the same object as b).
The eql? method returns true if obj and anObject have the same value. Used by Hash to test members for equality. For objects of class Object, eql? is synonymous with ==. Subclasses normally continue this tradition, but there are exceptions. Numeric types, for example, perform type conversion across ==, but not across eql?, so:
1 == 1.0 #=> true 1.eql? 1.0 #=> false
static VALUE
rb_obj_equal(obj1, obj2)
VALUE obj1, obj2;
{
if (obj1 == obj2) return Qtrue;
return Qfalse;
}
Case Equality—For class Object, effectively the same as calling #==, but typically overridden by descendents to provide meaningful semantics in case statements.
VALUE
rb_equal(obj1, obj2)
VALUE obj1, obj2;
{
VALUE result;
if (obj1 == obj2) return Qtrue;
result = rb_funcall(obj1, id_eq, 1, obj2);
if (RTEST(result)) return Qtrue;
return Qfalse;
}
Returns an integer identifier for obj. The same number will be returned on all calls to id for a given object, and no two active objects will share an id. Object#object_id is a different concept from the :name notation, which returns the symbol id of name. Replaces the deprecated Object#id.
VALUE
rb_obj_id(VALUE obj)
{
/*
* 32-bit VALUE space
* MSB ------------------------ LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol ssssssssssssssssssssssss00001110
* object oooooooooooooooooooooooooooooo00 = 0 (mod sizeof(RVALUE))
* fixnum fffffffffffffffffffffffffffffff1
*
* object_id space
* LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol 000SSSSSSSSSSSSSSSSSSSSSSSSSSS0 S...S % A = 4 (S...S = s...s * A + 4)
* object oooooooooooooooooooooooooooooo0 o...o % A = 0
* fixnum fffffffffffffffffffffffffffffff1 bignum if required
*
* where A = sizeof(RVALUE)/4
*
* sizeof(RVALUE) is
* 20 if 32-bit, double is 4-byte aligned
* 24 if 32-bit, double is 8-byte aligned
* 40 if 64-bit
*/
if (TYPE(obj) == T_SYMBOL) {
return (SYM2ID(obj) * sizeof(RVALUE) + (4 << 2)) | FIXNUM_FLAG;
}
if (SPECIAL_CONST_P(obj)) {
return LONG2NUM((long)obj);
}
return (VALUE)((long)obj|FIXNUM_FLAG);
}
Invokes the method identified by symbol, passing it any arguments specified. You can use __send__ if the name send clashes with an existing method in obj.
class Klass def hello(*args) "Hello " + args.join(' ') end end k = Klass.new k.send :hello, "gentle", "readers" #=> "Hello gentle readers"
static VALUE
rb_f_send(argc, argv, recv)
int argc;
VALUE *argv;
VALUE recv;
{
VALUE vid;
if (argc == 0) rb_raise(rb_eArgError, "no method name given");
vid = *argv++; argc--;
PUSH_ITER(rb_block_given_p()?ITER_PRE:ITER_NOT);
vid = rb_call(CLASS_OF(recv), recv, rb_to_id(vid), argc, argv, 1, Qundef);
POP_ITER();
return vid;
}
Returns the class of obj, now preferred over Object#type, as an object’s type in Ruby is only loosely tied to that object’s class. This method must always be called with an explicit receiver, as class is also a reserved word in Ruby.
1.class #=> Fixnum self.class #=> Object
VALUE
rb_obj_class(obj)
VALUE obj;
{
return rb_class_real(CLASS_OF(obj));
}
Produces a shallow copy of obj—the instance variables of obj are copied, but not the objects they reference. Copies the frozen and tainted state of obj. See also the discussion under Object#dup.
class Klass attr_accessor :str end s1 = Klass.new #=> #<Klass:0x401b3a38> s1.str = "Hello" #=> "Hello" s2 = s1.clone #=> #<Klass:0x401b3998 @str="Hello"> s2.str[1,4] = "i" #=> "i" s1.inspect #=> "#<Klass:0x401b3a38 @str=\"Hi\">" s2.inspect #=> "#<Klass:0x401b3998 @str=\"Hi\">"
This method may have class-specific behavior. If so, that behavior will be documented under the #initialize_copy method of the class.
VALUE
rb_obj_clone(obj)
VALUE obj;
{
VALUE clone;
if (rb_special_const_p(obj)) {
rb_raise(rb_eTypeError, "can't clone %s", rb_obj_classname(obj));
}
clone = rb_obj_alloc(rb_obj_class(obj));
RBASIC(clone)->klass = rb_singleton_class_clone(obj);
RBASIC(clone)->flags = (RBASIC(obj)->flags | FL_TEST(clone, FL_TAINT)) & ~(FL_FREEZE|FL_FINALIZE);
init_copy(clone, obj);
RBASIC(clone)->flags |= RBASIC(obj)->flags & FL_FREEZE;
return clone;
}
Prints obj on the given port (default $>). Equivalent to:
def display(port=$>) port.write self end
For example:
1.display "cat".display [ 4, 5, 6 ].display puts
produces:
1cat456
static VALUE
rb_obj_display(argc, argv, self)
int argc;
VALUE *argv;
VALUE self;
{
VALUE out;
if (rb_scan_args(argc, argv, "01", &out) == 0) {
out = rb_stdout;
}
rb_io_write(out, self);
return Qnil;
}
Produces a shallow copy of obj—the instance variables of obj are copied, but not the objects they reference. dup copies the tainted state of obj. See also the discussion under Object#clone. In general, clone and dup may have different semantics in descendent classes. While clone is used to duplicate an object, including its internal state, dup typically uses the class of the descendent object to create the new instance.
This method may have class-specific behavior. If so, that behavior will be documented under the #initialize_copy method of the class.
VALUE
rb_obj_dup(obj)
VALUE obj;
{
VALUE dup;
if (rb_special_const_p(obj)) {
rb_raise(rb_eTypeError, "can't dup %s", rb_obj_classname(obj));
}
dup = rb_obj_alloc(rb_obj_class(obj));
init_copy(dup, obj);
return dup;
}
Returns Enumerable::Enumerator.new(self, method, *args).
e.g.:
str = "xyz" enum = str.enum_for(:each_byte) a = enum.map {|b| '%02x' % b } #=> ["78", "79", "7a"] # protects an array from being modified a = [1, 2, 3] some_method(a.to_enum)
static VALUE
obj_to_enum(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE meth = sym_each;
if (argc > 0) {
--argc;
meth = *argv++;
}
return rb_enumeratorize(obj, meth, argc, argv);
}
Equality—At the Object level, == returns true only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
Unlike ==, the equal? method should never be overridden by subclasses: it is used to determine object identity (that is, a.equal?(b) iff a is the same object as b).
The eql? method returns true if obj and anObject have the same value. Used by Hash to test members for equality. For objects of class Object, eql? is synonymous with ==. Subclasses normally continue this tradition, but there are exceptions. Numeric types, for example, perform type conversion across ==, but not across eql?, so:
1 == 1.0 #=> true 1.eql? 1.0 #=> false
static VALUE
rb_obj_equal(obj1, obj2)
VALUE obj1, obj2;
{
if (obj1 == obj2) return Qtrue;
return Qfalse;
}
Equality—At the Object level, == returns true only if obj and other are the same object. Typically, this method is overridden in descendent classes to provide class-specific meaning.
Unlike ==, the equal? method should never be overridden by subclasses: it is used to determine object identity (that is, a.equal?(b) iff a is the same object as b).
The eql? method returns true if obj and anObject have the same value. Used by Hash to test members for equality. For objects of class Object, eql? is synonymous with ==. Subclasses normally continue this tradition, but there are exceptions. Numeric types, for example, perform type conversion across ==, but not across eql?, so:
1 == 1.0 #=> true 1.eql? 1.0 #=> false
static VALUE
rb_obj_equal(obj1, obj2)
VALUE obj1, obj2;
{
if (obj1 == obj2) return Qtrue;
return Qfalse;
}
Adds to obj the instance methods from each module given as a parameter.
module Mod def hello "Hello from Mod.\n" end end class Klass def hello "Hello from Klass.\n" end end k = Klass.new k.hello #=> "Hello from Klass.\n" k.extend(Mod) #=> #<Klass:0x401b3bc8> k.hello #=> "Hello from Mod.\n"
static VALUE
rb_obj_extend(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
int i;
if (argc == 0) {
rb_raise(rb_eArgError, "wrong number of arguments (0 for 1)");
}
for (i=0; i<argc; i++) Check_Type(argv[i], T_MODULE);
while (argc--) {
rb_funcall(argv[argc], rb_intern("extend_object"), 1, obj);
rb_funcall(argv[argc], rb_intern("extended"), 1, obj);
}
return obj;
}
Prevents further modifications to obj. A TypeError will be raised if modification is attempted. There is no way to unfreeze a frozen object. See also Object#frozen?.
a = [ "a", "b", "c" ] a.freeze a << "z"
produces:
prog.rb:3:in `<<': can't modify frozen array (TypeError) from prog.rb:3
VALUE
rb_obj_freeze(obj)
VALUE obj;
{
if (!OBJ_FROZEN(obj)) {
if (rb_safe_level() >= 4 && !OBJ_TAINTED(obj)) {
rb_raise(rb_eSecurityError, "Insecure: can't freeze object");
}
OBJ_FREEZE(obj);
}
return obj;
}
Returns the freeze status of obj.
a = [ "a", "b", "c" ] a.freeze #=> ["a", "b", "c"] a.frozen? #=> true
static VALUE
rb_obj_frozen_p(obj)
VALUE obj;
{
if (OBJ_FROZEN(obj)) return Qtrue;
return Qfalse;
}
Generates a Fixnum hash value for this object. This function must have the property that a.eql?(b) implies a.hash == b.hash. The hash value is used by class Hash. Any hash value that exceeds the capacity of a Fixnum will be truncated before being used.
VALUE
rb_obj_id(VALUE obj)
{
/*
* 32-bit VALUE space
* MSB ------------------------ LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol ssssssssssssssssssssssss00001110
* object oooooooooooooooooooooooooooooo00 = 0 (mod sizeof(RVALUE))
* fixnum fffffffffffffffffffffffffffffff1
*
* object_id space
* LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol 000SSSSSSSSSSSSSSSSSSSSSSSSSSS0 S...S % A = 4 (S...S = s...s * A + 4)
* object oooooooooooooooooooooooooooooo0 o...o % A = 0
* fixnum fffffffffffffffffffffffffffffff1 bignum if required
*
* where A = sizeof(RVALUE)/4
*
* sizeof(RVALUE) is
* 20 if 32-bit, double is 4-byte aligned
* 24 if 32-bit, double is 8-byte aligned
* 40 if 64-bit
*/
if (TYPE(obj) == T_SYMBOL) {
return (SYM2ID(obj) * sizeof(RVALUE) + (4 << 2)) | FIXNUM_FLAG;
}
if (SPECIAL_CONST_P(obj)) {
return LONG2NUM((long)obj);
}
return (VALUE)((long)obj|FIXNUM_FLAG);
}
Soon-to-be deprecated version of Object#object_id.
VALUE
rb_obj_id_obsolete(obj)
VALUE obj;
{
rb_warn("Object#id will be deprecated; use Object#object_id");
return rb_obj_id(obj);
}
Returns a string containing a human-readable representation of obj. If not overridden, uses the to_s method to generate the string.
[ 1, 2, 3..4, 'five' ].inspect #=> "[1, 2, 3..4, \"five\"]" Time.new.inspect #=> "Wed Apr 09 08:54:39 CDT 2003"
static VALUE
rb_obj_inspect(obj)
VALUE obj;
{
if (TYPE(obj) == T_OBJECT
&& ROBJECT(obj)->iv_tbl
&& ROBJECT(obj)->iv_tbl->num_entries > 0) {
VALUE str;
size_t len;
const char *c = rb_obj_classname(obj);
if (rb_inspecting_p(obj)) {
len = strlen(c)+10+16+1;
str = rb_str_new(0, len); /* 10:tags 16:addr 1:nul */
snprintf(RSTRING(str)->ptr, len, "#<%s:0x%lx ...>", c, obj);
RSTRING(str)->len = strlen(RSTRING(str)->ptr);
return str;
}
len = strlen(c)+6+16+1;
str = rb_str_new(0, len); /* 6:tags 16:addr 1:nul */
snprintf(RSTRING(str)->ptr, len, "-<%s:0x%lx", c, obj);
RSTRING(str)->len = strlen(RSTRING(str)->ptr);
return rb_protect_inspect(inspect_obj, obj, str);
}
return rb_funcall(obj, rb_intern("to_s"), 0, 0);
}
Evaluates a string containing Ruby source code, or the given block, within the context of the receiver (obj). In order to set the context, the variable self is set to obj while the code is executing, giving the code access to obj’s instance variables. In the version of instance_eval that takes a String, the optional second and third parameters supply a filename and starting line number that are used when reporting compilation errors.
class Klass def initialize @secret = 99 end end k = Klass.new k.instance_eval { @secret } #=> 99
VALUE
rb_obj_instance_eval(argc, argv, self)
int argc;
VALUE *argv;
VALUE self;
{
VALUE klass;
if (SPECIAL_CONST_P(self)) {
klass = Qnil;
}
else {
klass = rb_singleton_class(self);
}
return specific_eval(argc, argv, klass, self);
}
Executes the given block within the context of the receiver (obj). In order to set the context, the variable self is set to obj while the code is executing, giving the code access to obj’s instance variables. Arguments are passed as block parameters.
class KlassWithSecret def initialize @secret = 99 end end k = KlassWithSecret.new k.instance_exec(5) {|x| @secret+x } #=> 104
VALUE
rb_obj_instance_exec(argc, argv, self)
int argc;
VALUE *argv;
VALUE self;
{
VALUE klass;
if (SPECIAL_CONST_P(self)) {
klass = Qnil;
}
else {
klass = rb_singleton_class(self);
}
return yield_under(klass, self, rb_ary_new4(argc, argv));
}
Returns true if obj is an instance of the given class. See also Object#kind_of?.
VALUE
rb_obj_is_instance_of(obj, c)
VALUE obj, c;
{
switch (TYPE(c)) {
case T_MODULE:
case T_CLASS:
case T_ICLASS:
break;
default:
rb_raise(rb_eTypeError, "class or module required");
}
if (rb_obj_class(obj) == c) return Qtrue;
return Qfalse;
}
Returns true if the given instance variable is defined in obj.
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
static VALUE
rb_obj_ivar_defined(obj, iv)
VALUE obj, iv;
{
ID id = rb_to_id(iv);
if (!rb_is_instance_id(id)) {
rb_name_error(id, "`%s' is not allowed as an instance variable name", rb_id2name(id));
}
return rb_ivar_defined(obj, id);
}
Returns the value of the given instance variable, or nil if the instance variable is not set. The @ part of the variable name should be included for regular instance variables. Throws a NameError 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
static VALUE
rb_obj_ivar_get(obj, iv)
VALUE obj, iv;
{
ID id = rb_to_id(iv);
if (!rb_is_instance_id(id)) {
rb_name_error(id, "`%s' is not allowed as an instance variable name", rb_id2name(id));
}
return rb_ivar_get(obj, id);
}
Sets the instance variable names by symbol to object, 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\">"
static VALUE
rb_obj_ivar_set(obj, iv, val)
VALUE obj, iv, val;
{
ID id = rb_to_id(iv);
if (!rb_is_instance_id(id)) {
rb_name_error(id, "`%s' is not allowed as an instance variable name", rb_id2name(id));
}
return rb_ivar_set(obj, id, val);
}
Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.
class Fred attr_accessor :a1 def initialize @iv = 3 end end Fred.new.instance_variables #=> ["@iv"]
VALUE
rb_obj_instance_variables(obj)
VALUE obj;
{
VALUE ary;
ary = rb_ary_new();
switch (TYPE(obj)) {
case T_OBJECT:
case T_CLASS:
case T_MODULE:
if (ROBJECT(obj)->iv_tbl) {
st_foreach_safe(ROBJECT(obj)->iv_tbl, ivar_i, ary);
}
break;
default:
if (!generic_iv_tbl) break;
if (FL_TEST(obj, FL_EXIVAR) || rb_special_const_p(obj)) {
st_data_t tbl;
if (st_lookup(generic_iv_tbl, obj, &tbl)) {
st_foreach_safe((st_table *)tbl, ivar_i, ary);
}
}
break;
}
return ary;
}
Returns true if class is the class of obj, or if class is one of the superclasses of obj or modules included in obj.
module M; end class A include M end class B < A; end class C < B; end b = B.new b.instance_of? A #=> false b.instance_of? B #=> true b.instance_of? C #=> false b.instance_of? M #=> false b.kind_of? A #=> true b.kind_of? B #=> true b.kind_of? C #=> false b.kind_of? M #=> true
VALUE
rb_obj_is_kind_of(obj, c)
VALUE obj, c;
{
VALUE cl = CLASS_OF(obj);
switch (TYPE(c)) {
case T_MODULE:
case T_CLASS:
case T_ICLASS:
break;
default:
rb_raise(rb_eTypeError, "class or module required");
}
while (cl) {
if (cl == c || RCLASS(cl)->m_tbl == RCLASS(c)->m_tbl)
return Qtrue;
cl = RCLASS(cl)->super;
}
return Qfalse;
}
Returns true if class is the class of obj, or if class is one of the superclasses of obj or modules included in obj.
module M; end class A include M end class B < A; end class C < B; end b = B.new b.instance_of? A #=> false b.instance_of? B #=> true b.instance_of? C #=> false b.instance_of? M #=> false b.kind_of? A #=> true b.kind_of? B #=> true b.kind_of? C #=> false b.kind_of? M #=> true
VALUE
rb_obj_is_kind_of(obj, c)
VALUE obj, c;
{
VALUE cl = CLASS_OF(obj);
switch (TYPE(c)) {
case T_MODULE:
case T_CLASS:
case T_ICLASS:
break;
default:
rb_raise(rb_eTypeError, "class or module required");
}
while (cl) {
if (cl == c || RCLASS(cl)->m_tbl == RCLASS(c)->m_tbl)
return Qtrue;
cl = RCLASS(cl)->super;
}
return Qfalse;
}
Looks up the named method as a receiver in obj, returning a Method object (or raising NameError). The Method object acts as a closure in obj’s object instance, so instance variables and the value of self remain available.
class Demo def initialize(n) @iv = n end def hello() "Hello, @iv = #{@iv}" end end k = Demo.new(99) m = k.method(:hello) m.call #=> "Hello, @iv = 99" l = Demo.new('Fred') m = l.method("hello") m.call #=> "Hello, @iv = Fred"
VALUE
rb_obj_method(obj, vid)
VALUE obj;
VALUE vid;
{
return mnew(CLASS_OF(obj), obj, rb_to_id(vid), rb_cMethod);
}
Returns a list of the names of methods publicly accessible in obj. This will include all the methods accessible in obj’s ancestors.
class Klass def kMethod() end end k = Klass.new k.methods[0..9] #=> ["kMethod", "freeze", "nil?", "is_a?", "class", "instance_variable_set", "methods", "extend", "__send__", "instance_eval"] k.methods.length #=> 42
static VALUE
rb_obj_methods(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
retry:
if (argc == 0) {
VALUE args[1];
args[0] = Qtrue;
return rb_class_instance_methods(1, args, CLASS_OF(obj));
}
else {
VALUE recur;
rb_scan_args(argc, argv, "1", &recur);
if (RTEST(recur)) {
argc = 0;
goto retry;
}
return rb_obj_singleton_methods(argc, argv, obj);
}
}
call_seq:
nil.nil? => true <anything_else>.nil? => false
Only the object nil responds true to nil?.
static VALUE
rb_false(obj)
VALUE obj;
{
return Qfalse;
}
Returns an integer identifier for obj. The same number will be returned on all calls to id for a given object, and no two active objects will share an id. Object#object_id is a different concept from the :name notation, which returns the symbol id of name. Replaces the deprecated Object#id.
VALUE
rb_obj_id(VALUE obj)
{
/*
* 32-bit VALUE space
* MSB ------------------------ LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol ssssssssssssssssssssssss00001110
* object oooooooooooooooooooooooooooooo00 = 0 (mod sizeof(RVALUE))
* fixnum fffffffffffffffffffffffffffffff1
*
* object_id space
* LSB
* false 00000000000000000000000000000000
* true 00000000000000000000000000000010
* nil 00000000000000000000000000000100
* undef 00000000000000000000000000000110
* symbol 000SSSSSSSSSSSSSSSSSSSSSSSSSSS0 S...S % A = 4 (S...S = s...s * A + 4)
* object oooooooooooooooooooooooooooooo0 o...o % A = 0
* fixnum fffffffffffffffffffffffffffffff1 bignum if required
*
* where A = sizeof(RVALUE)/4
*
* sizeof(RVALUE) is
* 20 if 32-bit, double is 4-byte aligned
* 24 if 32-bit, double is 8-byte aligned
* 40 if 64-bit
*/
if (TYPE(obj) == T_SYMBOL) {
return (SYM2ID(obj) * sizeof(RVALUE) + (4 << 2)) | FIXNUM_FLAG;
}
if (SPECIAL_CONST_P(obj)) {
return LONG2NUM((long)obj);
}
return (VALUE)((long)obj|FIXNUM_FLAG);
}
Returns the list of private methods accessible to obj. If the all parameter is set to false, only those methods in the receiver will be listed.
static VALUE
rb_obj_private_methods(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
if (argc == 0) { /* hack to stop warning */
VALUE args[1];
args[0] = Qtrue;
return rb_class_private_instance_methods(1, args, CLASS_OF(obj));
}
return rb_class_private_instance_methods(argc, argv, CLASS_OF(obj));
}
Returns the list of protected methods accessible to obj. If the all parameter is set to false, only those methods in the receiver will be listed.
static VALUE
rb_obj_protected_methods(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
if (argc == 0) { /* hack to stop warning */
VALUE args[1];
args[0] = Qtrue;
return rb_class_protected_instance_methods(1, args, CLASS_OF(obj));
}
return rb_class_protected_instance_methods(argc, argv, CLASS_OF(obj));
}
Returns the list of public methods accessible to obj. If the all parameter is set to false, only those methods in the receiver will be listed.
static VALUE
rb_obj_public_methods(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
if (argc == 0) { /* hack to stop warning */
VALUE args[1];
args[0] = Qtrue;
return rb_class_public_instance_methods(1, args, CLASS_OF(obj));
}
return rb_class_public_instance_methods(argc, argv, CLASS_OF(obj));
}
Returns true> if obj responds to the given method. Private methods are included in the search only if the optional second parameter evaluates to true.
static VALUE
obj_respond_to(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE mid, priv;
ID id;
rb_scan_args(argc, argv, "11", &mid, &priv);
id = rb_to_id(mid);
if (rb_method_boundp(CLASS_OF(obj), id, !RTEST(priv))) {
return Qtrue;
}
return Qfalse;
}
Invokes the method identified by symbol, passing it any arguments specified. You can use __send__ if the name send clashes with an existing method in obj.
class Klass def hello(*args) "Hello " + args.join(' ') end end k = Klass.new k.send :hello, "gentle", "readers" #=> "Hello gentle readers"
static VALUE
rb_f_send(argc, argv, recv)
int argc;
VALUE *argv;
VALUE recv;
{
VALUE vid;
if (argc == 0) rb_raise(rb_eArgError, "no method name given");
vid = *argv++; argc--;
PUSH_ITER(rb_block_given_p()?ITER_PRE:ITER_NOT);
vid = rb_call(CLASS_OF(recv), recv, rb_to_id(vid), argc, argv, 1, Qundef);
POP_ITER();
return vid;
}
Returns an array of the names of singleton methods for obj. If the optional all parameter is true, the list will include methods in modules included in obj.
module Other def three() end end class Single def Single.four() end end a = Single.new def a.one() end class << a include Other def two() end end Single.singleton_methods #=> ["four"] a.singleton_methods(false) #=> ["two", "one"] a.singleton_methods #=> ["two", "one", "three"]
VALUE
rb_obj_singleton_methods(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE recur, ary, klass;
st_table *list;
rb_scan_args(argc, argv, "01", &recur);
if (argc == 0) {
recur = Qtrue;
}
klass = CLASS_OF(obj);
list = st_init_numtable();
if (klass && FL_TEST(klass, FL_SINGLETON)) {
st_foreach(RCLASS(klass)->m_tbl, method_entry, (st_data_t)list);
klass = RCLASS(klass)->super;
}
if (RTEST(recur)) {
while (klass && (FL_TEST(klass, FL_SINGLETON) || TYPE(klass) == T_ICLASS)) {
st_foreach(RCLASS(klass)->m_tbl, method_entry, (st_data_t)list);
klass = RCLASS(klass)->super;
}
}
ary = rb_ary_new();
st_foreach(list, ins_methods_i, ary);
st_free_table(list);
return ary;
}
Marks obj as tainted—if the $SAFE level is set appropriately, many method calls which might alter the running programs environment will refuse to accept tainted strings.
VALUE
rb_obj_taint(obj)
VALUE obj;
{
rb_secure(4);
if (!OBJ_TAINTED(obj)) {
if (OBJ_FROZEN(obj)) {
rb_error_frozen("object");
}
OBJ_TAINT(obj);
}
return obj;
}
Returns true if the object is tainted.
VALUE
rb_obj_tainted(obj)
VALUE obj;
{
if (OBJ_TAINTED(obj))
return Qtrue;
return Qfalse;
}
Yields x to the block, and then returns x. The primary purpose of this method is to “tap into” a method chain, in order to perform operations on intermediate results within the chain.
(1..10).tap { |x| puts "original: #{x.inspect}" }.to_a.tap { |x| puts "array: #{x.inspect}" }.select {|x| x%2==0}.tap { |x| puts "evens: #{x.inspect}" }.map {|x| x*x}.tap { |x| puts "squares: #{x.inspect}" }
VALUE
rb_obj_tap(obj)
VALUE obj;
{
rb_yield(obj);
return obj;
}
Returns an array representation of obj. For objects of class Object and others that don’t explicitly override the method, the return value is an array containing self. However, this latter behavior will soon be obsolete.
self.to_a #=> -:1: warning: default `to_a' will be obsolete "hello".to_a #=> ["hello"] Time.new.to_a #=> [39, 54, 8, 9, 4, 2003, 3, 99, true, "CDT"]
static VALUE
rb_any_to_a(obj)
VALUE obj;
{
rb_warn("default `to_a' will be obsolete");
return rb_ary_new3(1, obj);
}
Returns Enumerable::Enumerator.new(self, method, *args).
e.g.:
str = "xyz" enum = str.enum_for(:each_byte) a = enum.map {|b| '%02x' % b } #=> ["78", "79", "7a"] # protects an array from being modified a = [1, 2, 3] some_method(a.to_enum)
static VALUE
obj_to_enum(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE meth = sym_each;
if (argc > 0) {
--argc;
meth = *argv++;
}
return rb_enumeratorize(obj, meth, argc, argv);
}
Returns a string representing obj. The default to_s prints the object’s class and an encoding of the object id. As a special case, the top-level object that is the initial execution context of Ruby programs returns “main.”
VALUE
rb_any_to_s(obj)
VALUE obj;
{
const char *cname = rb_obj_classname(obj);
size_t len;
VALUE str;
len = strlen(cname)+6+16;
str = rb_str_new(0, len); /* 6:tags 16:addr */
snprintf(RSTRING(str)->ptr, len+1, "#<%s:0x%lx>", cname, obj);
RSTRING(str)->len = strlen(RSTRING(str)->ptr);
if (OBJ_TAINTED(obj)) OBJ_TAINT(str);
return str;
}
Deprecated synonym for Object#class.
VALUE
rb_obj_type(obj)
VALUE obj;
{
rb_warn("Object#type is deprecated; use Object#class");
return rb_class_real(CLASS_OF(obj));
}
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