Module: Deterministic::Monad
- Included in:
- Either, EnumBuilder::DataType::AnyEnum
- Defined in:
- lib/deterministic/monad.rb
Defined Under Namespace
Classes: NotMonadError
Instance Method Summary collapse
-
#==(other) ⇒ Object
Two monads are equivalent if they are of the same type and when their values are equal.
-
#bind(proc = nil, &block) ⇒ Object
(also: #>>=)
- The monad: takes a function which returns a monad (of the same type), applies the function bind
-
(a -> Mb) -> M a -> M b the self.class, i.e.
-
#fmap(proc = nil, &block) ⇒ Object
- The functor: takes a function (a -> b) and applies it to the inner value of the monad (Ma), boxes it back to the same monad (Mb) fmap
-
(a -> b) -> M a -> M b.
-
#initialize(init) ⇒ Object
Basicly the ‘pure` function.
-
#inspect ⇒ Object
Return the string representation of the Monad.
- #join(other) ⇒ Object
- #to_s ⇒ Object
-
#value ⇒ Object
- Get the underlying value, return in Haskell return
-
M a -> a.
Instance Method Details
#==(other) ⇒ Object
Two monads are equivalent if they are of the same type and when their values are equal
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# File 'lib/deterministic/monad.rb', line 66 def ==(other) return false unless other.is_a? self.class @value == other.instance_variable_get(:@value) end |
#bind(proc = nil, &block) ⇒ Object Also known as: >>=
The monad: takes a function which returns a monad (of the same type), applies the function
- bind
-
(a -> Mb) -> M a -> M b
the self.class, i.e. the containing monad is passed as a second (optional) arg to the function
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# File 'lib/deterministic/monad.rb', line 28 def bind(proc=nil, &block) (proc || block).call(value).tap do |result| # def parent_name(obj) # parts = obj.class.name.split('::') # if parts.count > 1 # parts[0..-2].join('::') # else # parts[0] # end # end # self_parent = parent_name(self) # other_parent = parent_name(result) # raise NotMonadError, "Expected #{result.inspect} to be an #{other_parent}" unless self_parent == other_parent parent = self.class.superclass === Object ? self.class : self.class.superclass raise NotMonadError, "Expected #{result.inspect} to be an #{parent}" unless result.is_a? parent end end |
#fmap(proc = nil, &block) ⇒ Object
The functor: takes a function (a -> b) and applies it to the inner value of the monad (Ma), boxes it back to the same monad (Mb)
- fmap
-
(a -> b) -> M a -> M b
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# File 'lib/deterministic/monad.rb', line 20 def fmap(proc=nil, &block) result = (proc || block).call(value) self.class.new(result) end |
#initialize(init) ⇒ Object
Basicly the ‘pure` function
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# File 'lib/deterministic/monad.rb', line 6 def initialize(init) @value = join(init) end |
#inspect ⇒ Object
Return the string representation of the Monad
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# File 'lib/deterministic/monad.rb', line 72 def inspect name = self.class.name.split("::")[-1] "#{name}(#{value})" end |
#join(other) ⇒ Object
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# File 'lib/deterministic/monad.rb', line 12 def join(other) if other.is_a? self.class then other.value else other end end |
#to_s ⇒ Object
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# File 'lib/deterministic/monad.rb', line 56 def to_s value.to_s end |
#value ⇒ Object
Get the underlying value, return in Haskell
- return
-
M a -> a
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# File 'lib/deterministic/monad.rb', line 52 def value @value end |