(use magic-pipes)
(use args)
(use ports)
(use chicken-syntax)

(receive (options operands before-exprs after-exprs usage)
         (parse-mp-args (command-line-arguments) '()
                        "predicate-expr"
                        "Read s-expressions from standard input, applies the
procedure-expr to them, and writes the s-expressions to
standard output if the predicate returned a true value.")
         (unless (= (length operands) 1)
                 (usage))
         (let* ((expr (parse-code (car operands)))
                (ec (make-eval-context before-exprs (list expr) after-exprs))
                (closure (eval-context-handler-closure ec 0)))
           (for-each-input-datum
            (lambda (input)
              (when (without-ports (lambda () (closure input)))
                    (data-write input)
                    (newline))))
           (without-input-port
            (eval-context-end-closure ec))))