^|EMal has a dedicated Logical type expressed by the logic keyword.
 |It's not nullable and holds the two values false and true.
 |There are no implicit conversions, but explicit conversions
 |from/to int (0,1) or text ("⊥", "⊤") are allowed.
 |^
logic booleanTrue = true
logic booleanFalse = false
if 2 > 1 and true and not false
  writeLine("true: " + true + ", false: " + false)
end
if false == logic!0
  writeLine("explicit conversion from integer")
end
if true == logic!"⊤"
  writeLine("explicit conversion from text")
end
writeLine(int!true) # is one
writeLine(text!false) # is "⊥"