Sometimes, you can use a feature called completion to help you enter arguments. This means that after you type part of the argument, Emacs can fill in the rest, or some of it, based on what you have typed so far.
When completion is available, certain keys (usually <TAB>, <RET>, and <SPC>) are rebound to complete the text in the minibuffer into a longer string chosen from a set of completion alternatives. The set of completion alternatives depends on the command that requested the argument, and on what you have typed so far. In addition, you can usually type ? to display a list of possible completions.
For example, M-x uses the minibuffer to read the name of a
command, so completion works by matching the minibuffer text against
the names of existing Emacs commands. So, to run the command
insert-buffer, you can type M-x ins <SPC> b <RET>
instead of the full M-x insert-buffer <RET>.
Case is significant in completion when it is significant in the argument you are entering, such as command names. Thus, ‘insert-buffer’ is not a valid completion for ‘IN’. Completion ignores case distinctions for certain arguments in which case does not matter.blog comments powered by Disqus