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+## std.booleans: Booleans and related types. Mostly compiler magic.
+## A stub module for documentation. Mostly compiler magic.
+
+pub type unit = union[sole]
+pub type bool = union[false, true]
+
+# note: puck could resolve kleene.false vs bool.false...
+# this is probably not worth it compared to improved type inference
+# pub type Kleene = union[False, Maybe, True]
+
+## Boolean equality
+pub func ==(a: bool, b: bool): bool =
+  match a
+  of (true, true), (false, false): true
+  of (false, true), (true, false): false
+
+pub func !=(a: bool, b: bool): bool =
+  not a == b
+
+## Boolean negation
+pub func not(a: bool): bool =
+  match a
+  of true: false
+  of false: true
+
+## Boolean conjunction
+pub func and(a: bool, b: bool): bool =
+  match (a, b)
+  of (true, true): true
+  of _: false
+
+## Boolean disjunction
+pub func or(a: bool, b: bool): bool =
+  match (a, b)
+  of (false, false): false
+  of _: true
+
+## Boolean exclusive disjunction
+pub func xor(a: bool, b: bool): bool =
+  match (a, b)
+  of (true, true), (false, false): false
+  of (true, false), (false, true): true