(when true
(map odd? (list 1 2 3)))

Question

(when true
  (map odd? (list 1 2 3)))

BlackTom AI · Accepted Answer

(Restating the question) You have the expression: (when true (map odd? (list 1 2 3))). The provided answer field shows (listof boolean) as the expected answer.

(First analysis step) The when form is a conditional that evaluates its body only if the test is true. Since the test here is true, the body will be evaluated.

(Second analysis step) The body is (map odd? (list 1 2 3)). Here, (list 1 2 3) constructs a list containing the integers 1, 2, and 3.

(Third analysis step) The map procedure applies the function odd? to each element of the list in order. Applying odd? to 1 yields true (or #t), to 2 yields false (or #f), and to 3 yields true (or #t).

(Fourth analysis step) Therefore, the result of the map expression is a list of booleans reflecting whether each corresponding input is odd: typically something like (true false true) or (#t #f #t), depending on the specific boolean literals used by the language variant.

(About the provided answer) The label (listof boolean) is not the concrete value produced by the expression; it appears to be a type signature indicating that the result is a list of boolean values. The actual value is a list of booleans, not the textual type description.

(Bringing it together) So, evaluating the entire expression yields a list of booleans corresponding to the oddness of 1, 2, and 3, and the fact that the prompt’s answer field shows a type signature suggests the expected response may be focusing on the result type rather than the exact literal representation of booleans. If you needed the exact concrete value, you would expect something like (true false true) or (#t #f #t) depending on the language's boolean syntax. If you instead must specify a type for the result, (listof boolean) correctly denotes that the result is a list whose elements are booleans.

(when true (map odd? (list 1 2 3)))

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