To work efficient the whitespace characters should be displayed.
After some problems to get a editing mode for my eclipse version and giving DLangIDE a try, I now use
emacs with the .d visualization and the combined Whitespace and D mode for ,dt Templates. Not perfect but ok.
My .emacs looks now this way:
(add-to-list 'auto-mode-alist '("\\.d$" . d-mode))
(add-to-list 'auto-mode-alist '("\\.dt$" . d-mode))
(add-to-list 'auto-mode-alist '("\\.dt$" . whitespace-mode))
(setq-default tab-width 4)
(setq whitespace-line-column 250)
followed by the d-mode.el code.:
;;; d-mode.el --- D Programming Language major mode for (X)Emacs
;;; Requires a cc-mode of version 5.30 or greater
;; Author: William Baxter
;; Contributors: Andrei Alexandrescu
;; Contributors: Russel Winder
;; Maintainer: Russel Winder <russel@winder.org.uk>
;; Created: March 2007
;; Version: 201512060745
;; Keywords: D programming language emacs cc-mode
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