[SOLVED] How does Emacs select which minor modes to list in the mode line?

How does Emacs select which minor modes to list in the mode line?

I plan to customize mode line in Emacs in near future, and i don't understand the algorithm behind listing minor modes in the mode line.

In section «1.3 The Mode Line» of Emacs manual it says: «MINOR is a list of some of the enabled "minor modes"»

While in section «23.2 Minor Modes» it says: «Most buffer-local minor modes say in the mode line when they are enabled»

However i have ErgoEmacs minor mode listed, which is global. Can somebody explain the mechanism behind this and preferably point at various elisp sources responsible for that?

Solution

This is specified for each individual mode, by the mode's own definition.

If you read on to section 23.3.3 - Defining Minor Modes:

The string LIGHTER says what to display in the mode line when the mode is enabled; if it is `nil', the mode is not displayed in the mode line.

See:

M-: (info "(elisp) Defining Minor Modes") RET

C-hf define-minor-mode RET

See also http://www.emacswiki.org/emacs/DelightedModes which facilitates easy customisation of the mode line display for both major and minor modes.