macro
boot.janet on line 293, column 1
(or & forms)
Evaluates to the last argument if all preceding elements are
falsey, otherwise evaluates to the first truthy element.
(or true) # => true
(or true true) # => true
(or true false) # => true
(or false 1 2) # => 1
(or false 2 1) # => 2
(or false nil) # => nil
(or nil false) # => false
# note that `or` does not behave as you might expect
# when used with `apply` and `splice`:
(or 1 2 3) # => 1
(or (splice [1 2 3])) # => (1 2 3)
(apply or [1 2 3]) # => (if 1 1 (if 2 2 3))