class NilClass - RDoc Documentation

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.

VALUE
rb_equal(VALUE obj1, VALUE obj2)
{
    VALUE result;

    if (obj1 == obj2) return Qtrue;
    result = rb_equal_opt(obj1, obj2);
    if (result == Qundef) {
        result = rb_funcall(obj1, id_eq, 1, obj2);
    }
    if (RTEST(result)) return Qtrue;
    return Qfalse;
}

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.

static VALUE
false_xor(VALUE obj, VALUE obj2)
{
    return RTEST(obj2)?Qtrue:Qfalse;
}

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 145
def to_d
  BigDecimal(0)
end

to_f → 0.0 click to toggle source

Always returns zero.

nil.to_f   #=> 0.0

static VALUE
nil_to_f(VALUE obj)
{
    return DBL2NUM(0.0);
}

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

static VALUE
nil_to_i(VALUE obj)
{
    return INT2FIX(0);
}

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.

static VALUE
false_or(VALUE obj, VALUE obj2)
{
    return RTEST(obj2)?Qtrue:Qfalse;
}