Plugging ledger pcomplete into completion-at-point.

Added documentation on how to use pcomplete transparently via completion-at-point.

doc/ledger-mode.texi

@@ -175,6 +175,11 @@ typing a close match to the payee. Ledger-mode will call @command{ledger
 xact} with the data you enter and place the transaction in the proper
 chronological place in the ledger.
 
+To complete just the part of the transaction where your cursor is at,
+Ledger-mode supports Emacs' universal @command{completion-at-point}
+command. You may bind this command to @kbd{C-M-i} since this is the
+default for Emacs programming modes.
+
 @node Reconciliation, Reports, Quick Add, Quick Demo
 @subsection Reconciliation
 @kindex C-c C-r

lisp/ledger-mode.el

@@ -325,6 +325,7 @@ With a prefix argument, remove the effective date. "
 			 'ledger-parse-arguments)
 	(set (make-local-variable 'pcomplete-command-completion-function)
 			 'ledger-complete-at-point)
+  (add-to-list 'completion-at-point-functions 'pcomplete-completions-at-point)
 
 	(add-hook 'post-command-hook 'ledger-highlight-xact-under-point nil t)
 	(add-hook 'before-revert-hook 'ledger-occur-remove-all-overlays nil t)