emacs: Use 'unless' instead of 'when' and 'not'

[notmuch] / emacs / notmuch-show.el

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index e6d7c9ea32cd6d3b19e720b430787a2130cf5150..7a03315027e088f721ad0d25bf46093ec3ba0d68 100644 (file)
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -506,10 +506,10 @@ message at DEPTH in the current thread."
 (defun notmuch-show-insert-part-header (nth content-type declared-type
                                            &optional name comment)
   (let ((button)
-       (base-label (concat (when name (concat name ": "))
+       (base-label (concat (and name (concat name ": "))
                            declared-type
-                           (unless (string-equal declared-type content-type)
-                             (concat " (as " content-type ")"))
+                           (and (not (string-equal declared-type content-type))
+                                (concat " (as " content-type ")"))
                            comment)))
     (setq button
          (insert-button
@@ -787,18 +787,15 @@ will return nil if the CID is unknown or cannot be retrieved."
 (defun notmuch-show-get-mime-type-of-application/octet-stream (part)
   ;; If we can deduce a MIME type from the filename of the attachment,
   ;; we return that.
-  (if (plist-get part :filename)
-      (let ((extension (file-name-extension (plist-get part :filename)))
-           mime-type)
-       (if extension
-           (progn
-             (mailcap-parse-mimetypes)
-             (setq mime-type (mailcap-extension-to-mime extension))
-             (if (and mime-type
-                      (not (string-equal mime-type "application/octet-stream")))
-                 mime-type
-               nil))
-         nil))))
+  (and (plist-get part :filename)
+       (let ((extension (file-name-extension (plist-get part :filename))))
+        (and extension
+             (progn
+               (mailcap-parse-mimetypes)
+               (let ((mime-type (mailcap-extension-to-mime extension)))
+                 (and mime-type
+                      (not (string-equal mime-type "application/octet-stream"))
+                      mime-type)))))))
 
 (defun notmuch-show-insert-part-text/html (msg part content-type nth depth button)
   (if (eq mm-text-html-renderer 'shr)
@@ -997,9 +994,10 @@ is t, hide the part initially and show the button."
         (beg (point))
         ;; This default header-p function omits the part button for
         ;; the first (or only) part if this is text/plain.
-        (button (when (funcall notmuch-show-insert-header-p-function part hide)
-                  (notmuch-show-insert-part-header nth mime-type content-type
-                                                   (plist-get part :filename))))
+        (button (and (funcall notmuch-show-insert-header-p-function part hide)
+                     (notmuch-show-insert-part-header
+                      nth mime-type content-type
+                      (plist-get part :filename))))
         ;; Hide the part initially if HIDE is t, or if it is too long
         ;; and we have a button to allow toggling.
         (show-part (not (or (equal hide t)
@@ -1054,9 +1052,8 @@ is t, hide the part initially and show the button."
         (bare-subject (notmuch-show-strip-re (plist-get headers :Subject))))
     (setq message-start (point-marker))
     (notmuch-show-insert-headerline headers
-                                   (or (if notmuch-show-relative-dates
-                                           (plist-get msg :date_relative)
-                                         nil)
+                                   (or (and notmuch-show-relative-dates
+                                            (plist-get msg :date_relative))
                                        (plist-get headers :Date))
                                    (plist-get msg :tags) depth)
     (setq content-start (point-marker))
@@ -1069,8 +1066,7 @@ is t, hide the part initially and show the button."
       ;; If the subject of this message is the same as that of the
       ;; previous message, don't display it when this message is
       ;; collapsed.
-      (when (not (string= notmuch-show-previous-subject
-                         bare-subject))
+      (unless (string= notmuch-show-previous-subject bare-subject)
        (forward-line 1))
       (setq headers-start (point-marker)))
     (setq headers-end (point-marker))
@@ -1303,8 +1299,8 @@ first relevant message.
 
 If no messages match the query return NIL."
   (let* ((cli-args (cons "--exclude=false"
-                        (when notmuch-show-elide-non-matching-messages
-                          (list "--entire-thread=false"))))
+                        (and notmuch-show-elide-non-matching-messages
+                             (list "--entire-thread=false"))))
         (queries (notmuch-show--build-queries
                   notmuch-show-thread-id notmuch-show-query-context))
         (forest nil)
@@ -2412,7 +2408,7 @@ MIME-TYPE is given then set the handle's mime-type to MIME-TYPE."
         (buf (notmuch-show-generate-part-buffer msg part))
         (computed-type (or mime-type (plist-get part :computed-type)))
         (filename (plist-get part :filename))
-        (disposition (if filename `(attachment (filename . ,filename)))))
+        (disposition (and filename `(attachment (filename . ,filename)))))
     (mm-make-handle buf (list computed-type) nil nil disposition)))
 
 (defun notmuch-show-apply-to-current-part-handle (fn &optional mime-type)