class NilClass

The class of the singleton object nil.

Public Instance Methods

false & obj → false click to toggle source
nil & obj → false

And—Returns false. obj is always evaluated as it is the argument to a method call—there is no short-circuit evaluation in this case.

static VALUE
false_and(VALUE obj, VALUE obj2)
{
    return Qfalse;
}
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
nil =~ other → nil click to toggle source

Dummy pattern matching – always returns nil.

static VALUE
nil_match(VALUE obj1, VALUE obj2)
{
    return Qnil;
}
false ^ obj → true or false click to toggle source
nil ^ obj → true or false

Exclusive Or—If obj is nil or false, returns false; otherwise, returns true.

#define false_xor true_and
inspect → "nil" click to toggle source

Always returns the string “nil”.

static VALUE
nil_inspect(VALUE obj)
{
    return rb_usascii_str_new2("nil");
}
nil? → true click to toggle source

Only the object nil responds true to nil?.

static VALUE
rb_true(VALUE obj)
{
    return Qtrue;
}
rationalize([eps]) → (0/1) click to toggle source

Returns zero as a rational. The optional argument eps is always ignored.

static VALUE
nilclass_rationalize(int argc, VALUE *argv, VALUE self)
{
    rb_check_arity(argc, 0, 1);
    return nilclass_to_r(self);
}
to_a → [] click to toggle source

Always returns an empty array.

nil.to_a   #=> []
static VALUE
nil_to_a(VALUE obj)
{
    return rb_ary_new2(0);
}
to_c → (0+0i) click to toggle source

Returns zero as a complex.

static VALUE
nilclass_to_c(VALUE self)
{
    return rb_complex_new1(INT2FIX(0));
}
to_d → bigdecimal click to toggle source

Returns nil represented as a BigDecimal.

require 'bigdecimal'
require 'bigdecimal/util'

nil.to_d   # => 0.0
# File ext/bigdecimal/lib/bigdecimal/util.rb, line 178
def to_d
  BigDecimal(0)
end
to_f → 0.0 click to toggle source

Always returns zero.

nil.to_f   #=> 0.0
# File nilclass.rb, line 22
def to_f
  return 0.0
end
to_h → {} click to toggle source

Always returns an empty hash.

nil.to_h   #=> {}
static VALUE
nil_to_h(VALUE obj)
{
    return rb_hash_new();
}
to_i → 0 click to toggle source

Always returns zero.

nil.to_i   #=> 0
# File nilclass.rb, line 10
def to_i
  return 0
end
to_r → (0/1) click to toggle source

Returns zero as a rational.

static VALUE
nilclass_to_r(VALUE self)
{
    return rb_rational_new1(INT2FIX(0));
}
to_s → "" click to toggle source

Always returns the empty string.

static VALUE
nil_to_s(VALUE obj)
{
    return rb_cNilClass_to_s;
}
false | obj → true or false click to toggle source
nil | obj → true or false

Or—Returns false if obj is nil or false; true otherwise.

#define false_or true_and