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The boolean module gives you the full set of classical logic gates as Lion functions. All binary operations take exactly two boolean arguments. The unary not takes a single boolean. Passing a non-boolean value produces a schema validation error.

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Functions

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boolean/not

Negates a boolean value. 
["boolean/not", true]
Result: false

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boolean/and

Returns true when both arguments are true. 
["boolean/and", true, false]
Result: false

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boolean/or

Returns true when at least one argument is true. 
["boolean/or", false, true]
Result: true

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boolean/xor

Returns true when exactly one argument is true (exclusive or). 
["boolean/xor", true, false]
Result: true 
["boolean/xor", true, true]
Result: false

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boolean/nand

Returns false only when both arguments are true (not-and). 
["boolean/nand", true, true]
Result: false 
["boolean/nand", true, false]
Result: true

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boolean/nor

Returns true only when both arguments are false (not-or). 
["boolean/nor", false, false]
Result: true 
["boolean/nor", false, true]
Result: false

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boolean/equals?

Returns true when both boolean values are identical. 
["boolean/equals?", true, true]
Result: true

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Composing boolean logic

Boolean operations nest naturally to express compound conditions: 
["boolean/and",
  ["number/greaterThan", "age", 18],
  ["boolean/not", "isBanned"]]
Prefer cond over deeply nested boolean/and/boolean/or chains when you have three or more conditions. It is easier to read and adds else fallback support.