Class: Object

Inherits:

BasicObject

Includes:

InstanceExecHelper

Defined in:

lib/ruby/try.rb,
lib/ruby/blank.rb,
lib/ruby/object.rb,
lib/ruby/instance_exec.rb

Defined Under Namespace

Modules: InstanceExecHelper

Combinators (collapse)

• - bind {|_self| ... }

  Yields self to a block argument.

• - tap {|_self| ... }

  Yields self to a side-effect block argument and return self.

• - try(*args, &block)

  Sends the arguments to self or yields self (when self is non-nil).

List Constructors (collapse)

• - (Array) cons(array = [])

  Prepend the item to the front of a new list.

• - (Array) snoc(array = [])

  Append the item to rear of a new list.

Instance Method Summary (collapse)

• - (Boolean) blank?

  Always false.

• - (Class) eigenclass

  Return the "eigenclass" where singleton methods reside.

• - instance_exec(*args, &block)
• - (Boolean) present?

nil.bind{|a| a.nil? }   #=> true
100.bind{|a| a.nil? }   #=> false

39
40
41

# File 'lib/ruby/object.rb', line 39

def bind
  yield self
end

false.blank?    #=> false
100.blank?      #=> false

60
61
62

# File 'lib/ruby/blank.rb', line 60

def blank?
  false
end

1.cons              #=> [1]
1.cons(2.cons)      #=> [1, 2]
1.cons([0, 0, 0])   #=> [1, 0, 0, 0]

14
15
16

# File 'lib/ruby/object.rb', line 14

def cons(array = [])
  [self] + array
end

60
61
62

# File 'lib/ruby/object.rb', line 60

def eigenclass
  class << self; self; end
end

8
9
10
11
12
13
14
15
16
17
18
19
20
21
22

# File 'lib/ruby/instance_exec.rb', line 8

def instance_exec(*args, &block)
  thread = Thread.current.object_id.abs
  object = object_id.abs
  mname  = "__instance_exec_#{thread}_#{object}"
  InstanceExecHelper.module_eval { define_method(mname, &block) }

  begin
    __send__(mname, *args)
  ensure
    begin
      InstanceExecHelper.module_eval { remove_method(mname) }
    rescue
    end
  end
end

64
65
66

# File 'lib/ruby/blank.rb', line 64

def present?
  true
end

1.snoc              #=> [1]
1.snoc(2.snoc)      #=> [2, 1]
1.snoc([0, 0, 0])   #=> [0, 0, 0, 1]

26
27
28

# File 'lib/ruby/object.rb', line 26

def snoc(array = [])
  array + [self]
end

49
50
51
52

# File 'lib/ruby/object.rb', line 49

def tap
  yield self
  self
end

"non-nil".try(&:length)       #=> 7
nil.try(&:length)             #=> nil

"non-nil".try(:slice, 0, 3)   #=> "non"
nil.try(:slice, 0, 3)         #=> nil

16
17
18
19
20
21
22

# File 'lib/ruby/try.rb', line 16

def try(*args, &block)
  if args.empty?
    yield self
  else
    __send__(*args, &block)
  end
end