class Object - RDoc Documentation (original) (raw)

Object is the default root of all Ruby objects. Object inherits from BasicObject which allows creating alternate object hierarchies. Methods on Object are available to all classes 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.

When referencing constants in classes inheriting from Object you do not need to use the full namespace. For example, referencing File inside YourClass will find the top-level File class.

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

ARGF

ARGF is a stream designed for use in scripts that process files given as command-line arguments or passed in via STDIN.

See ARGF (the class) for more details.

ARGV

ARGV contains the command line arguments used to run ruby.

A library like OptionParser can be used to process command-line arguments.

Bignum

An obsolete class, use Integer

CROSS_COMPILING

DATA

DATA is a File that contains the data section of the executed file. To create a data section use __END__:

$ cat t.rb puts DATA.gets END hello world!

$ ruby t.rb hello world!

ENV

ENV is a Hash-like accessor for environment variables.

See ENV (the class) for more details.

Fixnum

An obsolete class, use Integer

ParseError

RUBY_COPYRIGHT

The copyright string for ruby

RUBY_DESCRIPTION

The full ruby version string, like ruby -v prints

RUBY_ENGINE

The engine or interpreter this ruby uses.

RUBY_ENGINE_VERSION

The version of the engine or interpreter this ruby uses.

RUBY_PATCHLEVEL

The patchlevel for this ruby. If this is a development build of ruby the patchlevel will be -1

RUBY_PLATFORM

The platform for this ruby

RUBY_RELEASE_DATE

The date this ruby was released

RUBY_REVISION

The GIT commit hash for this ruby.

RUBY_VERSION

The running version of ruby

Readline

STDERR

Holds the original stderr

STDIN

Holds the original stdin

STDOUT

Holds the original stdout

TOPLEVEL_BINDING

The Binding of the top level scope

TimeoutError

Raised by Timeout.timeout when the block times out.

Public Class Methods

yaml_tag(url) click to toggle source

def self.yaml_tag url Psych.add_tag(url, self) end

Public Instance Methods

obj !~ other → true or false click to toggle source

Returns true if two objects do not match (using the =~ method), otherwise false.

static VALUE rb_obj_not_match(VALUE obj1, VALUE obj2) { VALUE result = rb_funcall(obj1, id_match, 1, obj2); return RTEST(result) ? Qfalse : Qtrue; }

obj <=> other → 0 or nil click to toggle source

Returns 0 if obj and other are the same object or obj == other, otherwise nil.

The #<=> is used by various methods to compare objects, for example Enumerable#sort, Enumerable#max etc.

Your implementation of #<=> should return one of the following values: -1, 0, 1 or nil. -1 means self is smaller than other. 0 means self is equal to other. 1 means self is bigger than other. Nil means the two values could not be compared.

When you define #<=>, you can include Comparable to gain the methods #<=, #<, #==, #>=, #> and between?.

static VALUE rb_obj_cmp(VALUE obj1, VALUE obj2) { if (rb_equal(obj1, obj2)) return INT2FIX(0); return Qnil; }

obj === other → true or false click to toggle source

Case Equality – For class Object, effectively the same as calling #==, but typically overridden by descendants to provide meaningful semantics in case statements.

#define case_equal rb_equal

obj =~ other → nil click to toggle source

This method is deprecated.

This is not only useless but also troublesome because it may hide a type error.

static VALUE rb_obj_match(VALUE obj1, VALUE obj2) { if (rb_warning_category_enabled_p(RB_WARN_CATEGORY_DEPRECATED)) { rb_category_warn(RB_WARN_CATEGORY_DEPRECATED, "deprecated Object#=~ is called on %"PRIsVALUE "; it always returns nil", rb_obj_class(obj1)); } return Qnil; }

CSV(*args, &block) click to toggle source

Passes args to CSV::instance.

CSV("CSV,data").read

If a block is given, the instance is passed the block and the return value becomes the return value of the block.

CSV("CSV,data") { |c| c.read.any? { |a| a.include?("data") } }

CSV("CSV,data") { |c| c.read.any? { |a| a.include?("zombies") } }

def CSV(*args, &block) CSV.instance(*args, &block) end

DelegateClass(superclass, &block) click to toggle source

The primary interface to this library. Use to setup delegation when defining your class.

class MyClass < DelegateClass(ClassToDelegateTo) def initialize super(obj_of_ClassToDelegateTo)
end end

or:

MyClass = DelegateClass(ClassToDelegateTo) do
def initialize super(obj_of_ClassToDelegateTo)
end end

Here's a sample of use from Tempfile which is really a File object with a few special rules about storage location and when the File should be deleted. That makes for an almost textbook perfect example of how to use delegation.

class Tempfile < DelegateClass(File)

def initialize(basename, tmpdir=Dir::tmpdir)

@tmpfile = File.open(tmpname, File::RDWR|File::CREAT|File::EXCL, 0600)


super(@tmpfile)

end

end

Calls superclass method

def DelegateClass(superclass, &block) klass = Class.new(Delegator) ignores = [*::Delegator.public_api, :to_s, :inspect, :=, :!, :===] protected_instance_methods = superclass.protected_instance_methods protected_instance_methods -= ignores public_instance_methods = superclass.public_instance_methods public_instance_methods -= ignores klass.module_eval do def getobj unless defined?(@delegate_dc_obj) return yield if block_given? raise ::ArgumentError, "not delegated" end @delegate_dc_obj end def setobj(obj)
raise ::ArgumentError, "cannot delegate to self" if self.equal?(obj) @delegate_dc_obj = obj end protected_instance_methods.each do |method| define_method(method, Delegator.delegating_block(method)) protected method end public_instance_methods.each do |method| define_method(method, Delegator.delegating_block(method)) end end klass.define_singleton_method :public_instance_methods do |all=true| super(all) | superclass.public_instance_methods end klass.define_singleton_method :protected_instance_methods do |all=true| super(all) | superclass.protected_instance_methods end klass.define_singleton_method :instance_methods do |all=true| super(all) | superclass.instance_methods end klass.define_singleton_method :public_instance_method do |name| super(name) rescue NameError raise unless self.public_instance_methods.include?(name) superclass.public_instance_method(name) end klass.define_singleton_method :instance_method do |name| super(name) rescue NameError raise unless self.instance_methods.include?(name) superclass.instance_method(name) end klass.module_eval(&block) if block return klass end

Digest(name) → digest_subclass click to toggle source

Returns a Digest subclass by name in a thread-safe manner even when on-demand loading is involved.

require 'digest'

Digest("MD5")

Digest(:SHA256)

Digest(:Foo)

def Digest(name) const = name.to_sym Digest::REQUIRE_MUTEX.synchronize {

Digest.const_missing(const)

} rescue LoadError

if Digest.const_defined?(const) Digest.const_get(const) else raise end end

define_singleton_method(symbol, method) → symbol click to toggle source

define_singleton_method(symbol) { block } → symbol

Defines a singleton method in the receiver. The method parameter can be a Proc, a Method or an UnboundMethod object. If a block is specified, it is used as the method body. If a block or a method has parameters, they're used as method parameters.

class A class << self def class_name to_s end end end A.define_singleton_method(:who_am_i) do "I am: #{class_name}" end A.who_am_i

guy = "Bob" guy.define_singleton_method(:hello) { "#{self}: Hello there!" } guy.hello

chris = "Chris" chris.define_singleton_method(:greet) {|greeting| "#{greeting}, I'm Chris!" } chris.greet("Hi")

static VALUE rb_obj_define_method(int argc, VALUE *argv, VALUE obj) { VALUE klass = rb_singleton_class(obj);

return rb_mod_define_method(argc, argv, klass);

}

display(port=$>) → nil click to toggle source

Prints obj on the given port (default $>). Equivalent to:

def display(port=$>) port.write self nil end

For example:

1.display "cat".display [ 4, 5, 6 ].display puts

produces:

1cat[4, 5, 6]

static VALUE rb_obj_display(int argc, VALUE *argv, VALUE self) { VALUE out;

out = (!rb_check_arity(argc, 0, 1) ? rb_ractor_stdout() : argv[0]);
rb_io_write(out, self);

return Qnil;

}

dup → an_object click to toggle source

Produces a shallow copy of _obj_—the instance variables of obj are copied, but not the objects they reference.

This method may have class-specific behavior. If so, that behavior will be documented under the #initialize_copy method of the class.

on dup vs clone¶ ↑

In general, clone and dup may have different semantics in descendant classes. While clone is used to duplicate an object, including its internal state, dup typically uses the class of the descendant object to create the new instance.

When using dup, any modules that the object has been extended with will not be copied.

class Klass attr_accessor :str end

module Foo def foo; 'foo'; end end

s1 = Klass.new s1.extend(Foo) s1.foo

s2 = s1.clone s2.foo

s3 = s1.dup s3.foo

VALUE rb_obj_dup(VALUE obj) { VALUE dup;

if (special_object_p(obj)) {
    return obj;
}
dup = rb_obj_alloc(rb_obj_class(obj));
init_copy(dup, obj);
rb_funcall(dup, id_init_dup, 1, obj);

return dup;

}

enum_for(method = :each, *args) → enum

enum_for(method = :each, *args){|*args| block} → enum

Creates a new Enumerator which will enumerate by calling method on obj, passing args if any. What was yielded by method becomes values of enumerator.

If a block is given, it will be used to calculate the size of the enumerator without the need to iterate it (see Enumerator#size).

Examples¶ ↑

str = "xyz"

enum = str.enum_for(:each_byte) enum.each { |b| puts b }

a = [1, 2, 3] some_method(a.to_enum)

very_large_string.split("|") { |chunk| return chunk if chunk.include?('DATE') }

very_large_string.to_enum(:split, "|").lazy.grep(/DATE/).first

It is typical to call to_enum when defining methods for a generic Enumerable, in case no block is passed.

Here is such an example, with parameter passing and a sizing block:

module Enumerable

def repeat(n) raise ArgumentError, "#{n} is negative!" if n < 0 unless block_given? return to_enum(method, n) do sz = size
sz * n if sz
end end each do |*val| n.times { yield *val } end end end

%i[hello world].repeat(2) { |w| puts w }

enum = (1..14).repeat(3)

enum.first(4) enum.size

obj == other → true or false click to toggle source

equal?(other) → true or false

eql?(other) → true or false

Equality — At the Object level, #== returns true only if obj and other are the same object. Typically, this method is overridden in descendant classes to provide class-specific meaning.

Unlike #==, the equal? method should never be overridden by subclasses as it is used to determine object identity (that is, a.equal?(b) if and only if a is the same object as b):

obj = "a" other = obj.dup

obj == other
obj.equal? other
obj.equal? obj

The eql? method returns true if obj and other refer to the same hash key. This is used by Hash to test members for equality. For any pair of objects where eql? returns true, the hash value of both objects must be equal. So any subclass that overrides eql? should also override hash appropriately.

For objects of class Object, eql? is synonymous with #==. Subclasses normally continue this tradition by aliasing eql? to their overridden #== method, but there are exceptions. Numeric types, for example, perform type conversion across #==, but not across eql?, so:

1 == 1.0
1.eql? 1.0

MJIT_FUNC_EXPORTED VALUE rb_obj_equal(VALUE obj1, VALUE obj2) { if (obj1 == obj2) return Qtrue; return Qfalse; }

extend(module, ...) → obj click to toggle source

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
k.extend(Mod)
k.hello

static VALUE rb_obj_extend(int argc, VALUE *argv, VALUE obj) { int i; ID id_extend_object, id_extended;

CONST_ID(id_extend_object, "extend_object");
CONST_ID(id_extended, "extended");

rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
for (i = 0; i < argc; i++)
    Check_Type(argv[i], T_MODULE);
while (argc--) {
    rb_funcall(argv[argc], id_extend_object, 1, obj);
    rb_funcall(argv[argc], id_extended, 1, obj);
}
return obj;

}

freeze → obj click to toggle source

Prevents further modifications to obj. A RuntimeError will be raised if modification is attempted. There is no way to unfreeze a frozen object. See also Object#frozen?.

This method returns self.

a = [ "a", "b", "c" ] a.freeze a << "z"

produces:

prog.rb:3:in `<<': can't modify frozen Array (FrozenError) from prog.rb:3

Objects of the following classes are always frozen: Integer, Float, Symbol.

VALUE rb_obj_freeze(VALUE obj) { if (!OBJ_FROZEN(obj)) { OBJ_FREEZE(obj); if (SPECIAL_CONST_P(obj)) { rb_bug("special consts should be frozen."); } } return obj; }

hash → integer click to toggle source

Generates an Integer 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 along with eql? by the Hash class to determine if two objects reference the same hash key. Any hash value that exceeds the capacity of an Integer will be truncated before being used.

The hash value for an object may not be identical across invocations or implementations of Ruby. If you need a stable identifier across Ruby invocations and implementations you will need to generate one with a custom method.

Certain core classes such as Integer use built-in hash calculations and do not call the hash method when used as a hash key.

VALUE rb_obj_hash(VALUE obj) { long hnum = any_hash(obj, objid_hash); return ST2FIX(hnum); }

inspect → string click to toggle source

Returns a string containing a human-readable representation of obj. The default inspect shows the object's class name, an encoding of its memory address, and a list of the instance variables and their values (by calling inspect on each of them). User defined classes should override this method to provide a better representation of obj. When overriding this method, it should return a string whose encoding is compatible with the default external encoding.

[ 1, 2, 3..4, 'five' ].inspect
Time.new.inspect

class Foo end Foo.new.inspect

class Bar def initialize @bar = 1 end end Bar.new.inspect

static VALUE rb_obj_inspect(VALUE obj) { if (rb_ivar_count(obj) > 0) { VALUE str; VALUE c = rb_class_name(CLASS_OF(obj));

    str = rb_sprintf("-<%"PRIsVALUE":%p", c, (void*)obj);
    return rb_exec_recursive(inspect_obj, obj, str);
}
else {
    return rb_any_to_s(obj);
}

}

instance_of?(class) → true or false click to toggle source

Returns true if obj is an instance of the given class. See also Object#kind_of?.

class A; end class B < A; end class C < B; end

b = B.new b.instance_of? A
b.instance_of? B
b.instance_of? C

VALUE rb_obj_is_instance_of(VALUE obj, VALUE c) { c = class_or_module_required(c); if (rb_obj_class(obj) == c) return Qtrue; return Qfalse; }

instance_variable_defined?(symbol) → true or false click to toggle source

instance_variable_defined?(string) → true or false

Returns true if the given instance variable is defined in obj. String arguments are converted to symbols.

class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_defined?(:@a)
fred.instance_variable_defined?("@b")
fred.instance_variable_defined?("@c")

static VALUE rb_obj_ivar_defined(VALUE obj, VALUE iv) { ID id = id_for_var(obj, iv, instance);

if (!id) {
    return Qfalse;
}
return rb_ivar_defined(obj, id);

}

instance_variable_get(symbol) → obj click to toggle source

instance_variable_get(string) → obj

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. String arguments are converted to symbols.

class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_get(:@a)
fred.instance_variable_get("@b")

static VALUE rb_obj_ivar_get(VALUE obj, VALUE iv) { ID id = id_for_var(obj, iv, instance);

if (!id) {
    return Qnil;
}
return rb_ivar_get(obj, id);

}

instance_variable_set(symbol, obj) → obj click to toggle source

instance_variable_set(string, obj) → obj

Sets the instance variable named by symbol to the given object. This may circumvent the encapsulation intended by the author of the class, so it should be used with care. The variable does not have to exist prior to this call. If the instance variable name is passed as a string, that string is converted to a symbol.

class Fred def initialize(p1, p2) @a, @b = p1, p2 end end fred = Fred.new('cat', 99) fred.instance_variable_set(:@a, 'dog')
fred.instance_variable_set(:@c, 'cat')
fred.inspect

static VALUE rb_obj_ivar_set(VALUE obj, VALUE iv, VALUE val) { ID id = id_for_var(obj, iv, instance); if (!id) id = rb_intern_str(iv); return rb_ivar_set(obj, id, val); }

instance_variables → array click to toggle source

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

VALUE rb_obj_instance_variables(VALUE obj) { VALUE ary;

ary = rb_ary_new();
rb_ivar_foreach(obj, ivar_i, ary);
return ary;

}

is_a?(class) → true or false

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.is_a? A
b.is_a? B
b.is_a? C
b.is_a? M

b.kind_of? A
b.kind_of? B
b.kind_of? C
b.kind_of? M

itself → obj click to toggle source

Returns the receiver.

string = "my string" string.itself.object_id == string.object_id

static VALUE rb_obj_itself(VALUE obj) { return obj; }

kind_of?(class) → true or false click to toggle source

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.is_a? A
b.is_a? B
b.is_a? C
b.is_a? M

b.kind_of? A
b.kind_of? B
b.kind_of? C
b.kind_of? M

VALUE rb_obj_is_kind_of(VALUE obj, VALUE c) { VALUE cl = CLASS_OF(obj);

c = class_or_module_required(c);
return class_search_ancestor(cl, RCLASS_ORIGIN(c)) ? Qtrue : Qfalse;

}

Also aliased as: is_a?

method(sym) → method click to toggle source

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

l = Demo.new('Fred') m = l.method("hello") m.call

Note that Method implements to_proc method, which means it can be used with iterators.

[ 1, 2, 3 ].each(&method(:puts))

out = File.open('test.txt', 'w') [ 1, 2, 3 ].each(&out.method(:puts))

require 'date' %w[2017-03-01 2017-03-02].collect(&Date.method(:parse))

VALUE rb_obj_method(VALUE obj, VALUE vid) { return obj_method(obj, vid, FALSE); }

methods(regular=true) → array click to toggle source

Returns a list of the names of public and protected methods of obj. This will include all the methods accessible in obj's ancestors. If the optional parameter is false, it returns an array of obj's public and protected singleton methods, the array will not include methods in modules included in obj.

class Klass def klass_method() end end k = Klass.new k.methods[0..9]

k.methods.length

k.methods(false)
def k.singleton_method; end k.methods(false)

module M123; def m123; end end k.extend M123 k.methods(false)

VALUE rb_obj_methods(int argc, const VALUE *argv, VALUE obj) { rb_check_arity(argc, 0, 1); if (argc > 0 && !RTEST(argv[0])) { return rb_obj_singleton_methods(argc, argv, obj); } return class_instance_method_list(argc, argv, CLASS_OF(obj), 1, ins_methods_i); }

nil? → true or false click to toggle source

Only the object nil responds true to nil?.

Object.new.nil?
nil.nil?

MJIT_FUNC_EXPORTED VALUE rb_false(VALUE obj) { return Qfalse; }

__id__ → integer click to toggle source

object_id → integer

Returns an integer identifier for obj.

The same number will be returned on all calls to object_id for a given object, and no two active objects will share an id.

Note: that some objects of builtin classes are reused for optimization. This is the case for immediate values and frozen string literals.

BasicObject implements +__id__+, Kernel implements object_id.

Immediate values are not passed by reference but are passed by value: nil, true, false, Fixnums, Symbols, and some Floats.

Object.new.object_id == Object.new.object_id
(21 * 2).object_id == (21 * 2).object_id
"hello".object_id == "hello".object_id
"hi".freeze.object_id == "hi".freeze.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 */

return rb_find_object_id(obj, cached_object_id);

}

private_methods(all=true) → array click to toggle source

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.

VALUE rb_obj_private_methods(int argc, const VALUE *argv, VALUE obj) { return class_instance_method_list(argc, argv, CLASS_OF(obj), 1, ins_methods_priv_i); }

protected_methods(all=true) → array click to toggle source

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.

VALUE rb_obj_protected_methods(int argc, const VALUE *argv, VALUE obj) { return class_instance_method_list(argc, argv, CLASS_OF(obj), 1, ins_methods_prot_i); }

public_method(sym) → method click to toggle source

Similar to method, searches public method only.

VALUE rb_obj_public_method(VALUE obj, VALUE vid) { return obj_method(obj, vid, TRUE); }

public_methods(all=true) → array click to toggle source

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.

VALUE rb_obj_public_methods(int argc, const VALUE *argv, VALUE obj) { return class_instance_method_list(argc, argv, CLASS_OF(obj), 1, ins_methods_pub_i); }

public_send(symbol [, args...]) → obj click to toggle source

public_send(string [, args...]) → obj

Invokes the method identified by symbol, passing it any arguments specified. Unlike send, public_send calls public methods only. When the method is identified by a string, the string is converted to a symbol.

1.public_send(:puts, "hello")

static VALUE rb_f_public_send(int argc, VALUE *argv, VALUE recv) { return send_internal_kw(argc, argv, recv, CALL_PUBLIC); }

remove_instance_variable(symbol) → obj click to toggle source

remove_instance_variable(string) → obj

Removes the named instance variable from obj, returning that variable's value. String arguments are converted to symbols.

class Dummy attr_reader :var def initialize @var = 99 end def remove remove_instance_variable(:@var) end end d = Dummy.new d.var
d.remove
d.var

VALUE rb_obj_remove_instance_variable(VALUE obj, VALUE name) { VALUE val = Qnil; const ID id = id_for_var(obj, name, an, instance); st_data_t n, v; struct st_table *iv_index_tbl; uint32_t index;

rb_check_frozen(obj);
if (!id) {
goto not_defined;
}

switch (BUILTIN_TYPE(obj)) {
  case T_OBJECT:
    iv_index_tbl = ROBJECT_IV_INDEX_TBL(obj);
    if (iv_index_tbl_lookup(iv_index_tbl, id, &index) &&
        index < ROBJECT_NUMIV(obj) &&
        (val = ROBJECT_IVPTR(obj)[index]) != Qundef) {
        ROBJECT_IVPTR(obj)[index] = Qundef;
        return val;
    }
break;
  case T_CLASS:
  case T_MODULE:
    IVAR_ACCESSOR_SHOULD_BE_MAIN_RACTOR(id);
n = id;
if (RCLASS_IV_TBL(obj) && st_delete(RCLASS_IV_TBL(obj), &n, &v)) {
    return (VALUE)v;
}
break;
  default:
if (FL_TEST(obj, FL_EXIVAR)) {
    if (generic_ivar_remove(obj, id, &val)) {
    return val;
    }
}
break;
}

not_defined: rb_name_err_raise("instance variable %1$s not defined", obj, name); UNREACHABLE_RETURN(Qnil); }

respond_to?(symbol, include_all=false) → true or false click to toggle source

respond_to?(string, include_all=false) → true or false

Returns true if obj responds to the given method. Private and protected methods are included in the search only if the optional second parameter evaluates to true.

If the method is not implemented, as Process.fork on Windows, File.lchmod on GNU/Linux, etc., false is returned.

If the method is not defined, respond_to_missing? method is called and the result is returned.

When the method name parameter is given as a string, the string is converted to a symbol.

static VALUE obj_respond_to(int argc, VALUE *argv, VALUE obj) { VALUE mid, priv; ID id; rb_execution_context_t *ec = GET_EC();

rb_scan_args(argc, argv, "11", &mid, &priv);
if (!(id = rb_check_id(&mid))) {
    VALUE ret = basic_obj_respond_to_missing(ec, CLASS_OF(obj), obj,
                                             rb_to_symbol(mid), priv);
    if (ret == Qundef) ret = Qfalse;
    return ret;
}
if (basic_obj_respond_to(ec, obj, id, !RTEST(priv)))
    return Qtrue;
return Qfalse;

}

respond_to_missing?(symbol, include_all) → true or false click to toggle source

respond_to_missing?(string, include_all) → true or false

DO NOT USE THIS DIRECTLY.

Hook method to return whether the obj can respond to id method or not.

When the method name parameter is given as a string, the string is converted to a symbol.

See respond_to?, and the example of BasicObject.

static VALUE obj_respond_to_missing(VALUE obj, VALUE mid, VALUE priv) { return Qfalse; }

send(symbol [, args...]) → obj click to toggle source

__send__(symbol [, args...]) → obj

send(string [, args...]) → obj

__send__(string [, args...]) → obj

Invokes the method identified by symbol, passing it any arguments specified. When the method is identified by a string, the string is converted to a symbol.

BasicObject implements +__send__+, Kernel implements send. __send__ is safer than send when obj has the same method name like Socket. See also public_send.

class Klass def hello(*args) "Hello " + args.join(' ') end end k = Klass.new k.send :hello, "gentle", "readers"

VALUE rb_f_send(int argc, VALUE *argv, VALUE recv) { return send_internal_kw(argc, argv, recv, CALL_FCALL); }

singleton_class → class click to toggle source

Returns the singleton class of obj. This method creates a new singleton class if obj does not have one.

If obj is nil, true, or false, it returns NilClass, TrueClass, or FalseClass, respectively. If obj is an Integer, a Float or a Symbol, it raises a TypeError.

Object.new.singleton_class
String.singleton_class
nil.singleton_class

static VALUE rb_obj_singleton_class(VALUE obj) { return rb_singleton_class(obj); }

singleton_method(sym) → method click to toggle source

Similar to method, searches singleton method only.

class Demo def initialize(n) @iv = n end def hello() "Hello, @iv = #{@iv}" end end

k = Demo.new(99) def k.hi "Hi, @iv = #{@iv}" end m = k.singleton_method(:hi) m.call
m = k.singleton_method(:hello)

VALUE rb_obj_singleton_method(VALUE obj, VALUE vid) { VALUE klass = rb_singleton_class_get(obj); ID id = rb_check_id(&vid);

if (NIL_P(klass)) {
    /* goto undef; */
}
else if (NIL_P(klass = RCLASS_ORIGIN(klass))) {
    /* goto undef; */
}
else if (! id) {
    VALUE m = mnew_missing_by_name(klass, obj, &vid, FALSE, rb_cMethod);
    if (m) return m;
    /* else goto undef; */
}
else {
    const rb_method_entry_t *me = rb_method_entry_at(klass, id);
    vid = ID2SYM(id);

    if (UNDEFINED_METHOD_ENTRY_P(me)) {
        /* goto undef; */
    }
    else if (UNDEFINED_REFINED_METHOD_P(me->def)) {
        /* goto undef; */
    }
    else {
        return mnew_from_me(me, klass, klass, obj, id, rb_cMethod, FALSE);
    }
}

/* undef: */ rb_name_err_raise("undefined singleton method %1$s' for %2$s'", obj, vid); UNREACHABLE_RETURN(Qundef); }

singleton_methods(all=true) → array click to toggle source

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. Only public and protected singleton methods are returned.

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
a.singleton_methods(false)
a.singleton_methods

VALUE rb_obj_singleton_methods(int argc, const VALUE *argv, VALUE obj) { VALUE ary, klass, origin; struct method_entry_arg me_arg; struct rb_id_table *mtbl; int recur = TRUE;

if (rb_check_arity(argc, 0, 1)) recur = RTEST(argv[0]);
if (RB_TYPE_P(obj, T_CLASS) && FL_TEST(obj, FL_SINGLETON)) {
    rb_singleton_class(obj);
}
klass = CLASS_OF(obj);
origin = RCLASS_ORIGIN(klass);
me_arg.list = st_init_numtable();
me_arg.recur = recur;
if (klass && FL_TEST(klass, FL_SINGLETON)) {
if ((mtbl = RCLASS_M_TBL(origin)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
klass = RCLASS_SUPER(klass);
}
if (recur) {
while (klass && (FL_TEST(klass, FL_SINGLETON) || RB_TYPE_P(klass, T_ICLASS))) {
    if (klass != origin && (mtbl = RCLASS_M_TBL(klass)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
    klass = RCLASS_SUPER(klass);
}
}
ary = rb_ary_new2(me_arg.list->num_entries);
st_foreach(me_arg.list, ins_methods_i, ary);
st_free_table(me_arg.list);

return ary;

}

taint → obj click to toggle source

Returns object. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_taint(VALUE obj) { rb_warn_deprecated_to_remove("Object#taint", "3.2"); return obj; }

tainted? → false click to toggle source

Returns false. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_tainted(VALUE obj) { rb_warn_deprecated_to_remove("Object#tainted?", "3.2"); return Qfalse; }

timeout(*args, &block) click to toggle source

def timeout(*args, &block) warn "Object##{method} is deprecated, use Timeout.timeout instead.", uplevel: 1 Timeout.timeout(*args, &block) end

to_enum(method = :each, *args) → enum click to toggle source

to_enum(method = :each, *args) {|*args| block} → enum

Creates a new Enumerator which will enumerate by calling method on obj, passing args if any. What was yielded by method becomes values of enumerator.

If a block is given, it will be used to calculate the size of the enumerator without the need to iterate it (see Enumerator#size).

Examples¶ ↑

str = "xyz"

enum = str.enum_for(:each_byte) enum.each { |b| puts b }

a = [1, 2, 3] some_method(a.to_enum)

very_large_string.split("|") { |chunk| return chunk if chunk.include?('DATE') }

very_large_string.to_enum(:split, "|").lazy.grep(/DATE/).first

It is typical to call to_enum when defining methods for a generic Enumerable, in case no block is passed.

Here is such an example, with parameter passing and a sizing block:

module Enumerable

def repeat(n) raise ArgumentError, "#{n} is negative!" if n < 0 unless block_given? return to_enum(method, n) do sz = size
sz * n if sz
end end each do |*val| n.times { yield *val } end end end

%i[hello world].repeat(2) { |w| puts w }

enum = (1..14).repeat(3)

enum.first(4) enum.size

static VALUE obj_to_enum(int argc, VALUE *argv, VALUE obj) { VALUE enumerator, meth = sym_each;

if (argc > 0) {
    --argc;
    meth = *argv++;
}
enumerator = rb_enumeratorize_with_size(obj, meth, argc, argv, 0);
if (rb_block_given_p()) {
    enumerator_ptr(enumerator)->size = rb_block_proc();
}
return enumerator;

}

to_s → string click to toggle source

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(VALUE obj) { VALUE str; VALUE cname = rb_class_name(CLASS_OF(obj));

str = rb_sprintf("#<%"PRIsVALUE":%p>", cname, (void*)obj);

return str;

}

to_yaml(options = {}) click to toggle source

Convert an object to YAML. See Psych.dump for more information on the available options.

def to_yaml options = {} Psych.dump self, options end

trust → obj click to toggle source

Returns object. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_trust(VALUE obj) { rb_warn_deprecated_to_remove("Object#trust", "3.2"); return obj; }

untaint → obj click to toggle source

Returns object. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_untaint(VALUE obj) { rb_warn_deprecated_to_remove("Object#untaint", "3.2"); return obj; }

untrust → obj click to toggle source

Returns object. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_untrust(VALUE obj) { rb_warn_deprecated_to_remove("Object#untrust", "3.2"); return obj; }

untrusted? → false click to toggle source

Returns false. This method is deprecated and will be removed in Ruby 3.2.

VALUE rb_obj_untrusted(VALUE obj) { rb_warn_deprecated_to_remove("Object#untrusted?", "3.2"); return Qfalse; }

xmp(exps, bind = nil) click to toggle source

A convenience method that's only available when the you require the IRB::XMP standard library.

Creates a new XMP object, using the given expressions as the exps parameter, and optional binding as bind or uses the top-level binding. Then evaluates the given expressions using the :XMP prompt mode.

For example:

require 'irb/xmp' ctx = binding xmp 'foo = "bar"', ctx

ctx.eval 'foo'

See XMP.new for more information.

def xmp(exps, bind = nil) bind = IRB::Frame.top(1) unless bind xmp = XMP.new(bind) xmp.puts exps xmp end