Boolean.hs

{-# LANGUAGE QuasiQuotes #-}
module Atomo.Kernel.Boolean (load) where

import Atomo.Environment
import Atomo.Haskell


load :: VM ()
load = mapM_ eval [$es|
    Boolean = Object clone
    True = Object clone
    False = Object clone

    True delegates-to: Boolean
    False delegates-to: Boolean

    True && True = True
    Boolean && Boolean = False

    False and: _ = False
    True and: (b: Block) := b call

    True || Boolean = True
    False || (b: Boolean) := b

    True or: _ = True
    False or: (b: Block) := b call

    True not := False
    False not := True

    if: True then: (a: Block) else: Block :=
      a call

    if: False then: Block else: (b: Block) :=
      b call

    when: False do: Block = @ok
    when: True do: (action: Block) :=
      { action in-context call
        @ok
      } call

    while: (test: Block) do: (action: Block) :=
      when: test call do:
        { action in-context call
          while: test do: action
        }

    True show := "True"
    False show := "False"

    otherwise := True

    condition: (b: Block) :=
      if: b contents empty?
        then: { raise: @no-true-branches }
        else: {
          es = b contents
          [c, e] = es head targets

          if: (c evaluate-in: b context)
            then: { e evaluate-in: b context }
            else: { condition: (Block new: es tail in: b context) }
        }
|]