conditional thread last (cond->>)

->> macro with conditional forms

Like ->>, but each form is paired with a test condition. The form is only applied if the test evaluates to true. Each test is evaluated with the current threaded value in scope.

An Example

(cond->> [1 2 3 4 5]
         [seq?    (map (lambda (x) (\* x 2)))]  ; doubles: [2 4 6 8 10]
         [!empty? (filter even?)]              ; keeps evens: [2 4 6 8 10]
         [(> 2)   (take 3)]                    ; takes first 3: [2 4 6]
         [false   (concat [0])])               ; skipped

Another Example

(cond->> [1 2 3]
         [seq?   (filter even?)]  ; predicate true, filters to [2]
         [empty? (concat [4 5])]  ; predicate false, skips concat
         [true   (take 1)])       ; takes first element