esh-cmd.el

(defun eshell-lisp-command (object &optional args)
  "Insert Lisp OBJECT, using ARGS if a function."
  (unless eshell-allow-commands
    (signal 'eshell-commands-forbidden '(lisp)))
  (catch 'eshell-external               ; deferred to an external command
    (when (memq eshell-in-pipeline-p '(nil last))
      (eshell-set-exit-info 0))
    (setq eshell-last-arguments args)
    (let* ((eshell-ensure-newline-p t)
           (command-form-p (functionp object))
           (result
            (if command-form-p
                (let ((numeric (not (get object
                                         'eshell-no-numeric-conversions)))
                      (fname-args (get object 'eshell-filename-arguments)))
                  (when (or numeric fname-args)
                    (while args
                      (let ((arg (car args)))
                        (cond
                         ((and numeric (eshell--numeric-string-p arg))
                          ;; If any of the arguments are flagged as
                          ;; numbers waiting for conversion, convert
                          ;; them now.
                          (setcar args (string-to-number arg)))
                         ((and fname-args (stringp arg)
                               (string-equal arg "~"))
                          ;; If any of the arguments match "~",
                          ;; prepend "./" to treat it as a regular
                          ;; file name.
                          (setcar args (concat "./" arg)))))
                      (setq args (cdr args))))
                  (setq eshell-last-command-name
                        (concat "#<function " (symbol-name object) ">"))
                  (eshell-apply* #'eshell-print-maybe-n
                                 #'eshell-error-maybe-n
                                 object eshell-last-arguments))
              (setq eshell-last-command-name "#<Lisp object>")
              (eshell-eval* #'eshell-print-maybe-n
                            #'eshell-error-maybe-n
                            object))))
      (when (memq eshell-in-pipeline-p '(nil last))
        (eshell-set-exit-info
         ;; If `eshell-lisp-form-nil-is-failure' is non-nil, Lisp forms
         ;; that succeeded but have a nil result should have an exit
         ;; status of 2.
         (when (and eshell-lisp-form-nil-is-failure
                    (not command-form-p)
                    (= eshell-last-command-status 0)
                    (not result))
           2)
         result))
      (and (eshell-function-target-p result)
           result))))