A compile-time literal is a fixed value that `case` can use as a test without evaluating a test expression. `case` evaluates its input, selects a matching branch, and evaluates that branch’s result. Its constant lookup is intended for faster branching than a linear `cond` test. section 3.3.4
A literal test
`(case 1 0 "zero" 1 "one" :other)` returns `"one"`. The test `1` is a literal; the result form is evaluated only when its test matches. section 3.3.4
Tests can include keywords, numbers, strings, characters, ratios, regexes, and collection literals. Do not use `(inc 0)` expecting it to become the test `1`: `case` does not evaluate that form as an expression. Parenthesized tests instead group alternatives for inclusion. Repeated test constants are an error; without a match, `case` returns its default or throws if none is supplied. section 3.3.4
