Apply a window configuration declaritively.

winconf.el

(defun -apply-window-configuration (conf window)
  (defun -split-to-windows (conf window)
    (if (null conf)
        nil
      (let* ((this-split (car conf))
            (new-window
             (cond ((eq (car this-split) 'column)
                    (split-window-right nil window))
                   ((eq (car this-split) 'row)
                    (split-window-below nil window))
                   (t (error (format "Invalid window split direction %s"
                                     this-split))))))
        (cons new-window (-split-to-windows (cdr conf) new-window)))))

  (defun split-to-windows (conf window)
    (cons window (-split-to-windows (cdr conf) window)))

  (defun apply-configuration-in-sub-windows (conf sub-windows)
    (if (null conf)
        nil
      (-apply-window-configuration (cdr (car conf)) (car sub-windows))
      (apply-configuration-in-sub-windows (cdr conf) (cdr sub-windows))))

  (if (null conf)
      nil
    (apply-configuration-in-sub-windows
     conf
     (split-to-windows conf window))))

(defun apply-window-configuration (conf)
  "Apply a configuration to the current frame. A configuration is a
list of columns or rows with their own configuration. For
example:

- ((row) (row))

  Splits the current frame into two rows.

- ((column) (column) (column))

  Splits the current frame into three columns.

- ((column) (column . ((row) (row))))

  Splits the current frame into this configuration:

  ┌─────┬─────┐
  │     │     │
  │     ├─────┤
  │     │     │
  └─────┴─────┘

- ((row)
   (row . ((column)
           (column . ((row) (row)))
           (column)))
   (row))

  Splits the current frame into this configuration:

  ┌────────────┐
  │            │
  ├───┬────┬───┤
  │   │    │   │
  │   ├────┤   │
  │   │    │   │
  ├───┴────┴───┤
  │            │
  └────────────┘
"
  (delete-other-windows)
  (-apply-window-configuration conf (selected-window))
  (balance-windows))