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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
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