To install this package from Emacs, use
The code provides a abbreviation expansion for Emacs. Its fairly similar to "dabbrev" expansion, which works based on the contents of the current buffer (or other buffers). Predictive abbreviation expansion works based on the previously written text. Unlike dynamic abbreviation, the text is analysed during idle time, while Emacs is doing nothing else. `pabbrev-mode' tells you when this is happening. If this irritates you unset `pabbrev-idle-timer-verbose'. The advantage of this is that its very quick to look up potential abbreviations, which means that they can be constantly displayed, without interfering with the user as they type. Certainly it works for me, on an old laptop, typing as fast as I can (which is fast, since I learnt to type with four fingers). pabbrev's main entry point is through the minor mode `pabbrev-mode'. There is also a global minor mode, called `global-pabbrev-mode', which does the same in all appropriate buffers. The current user interface looks like so... p[oint] pr[ogn] pre[-command-hook] pred[ictive] As the user types the system narrows down the possibilities. The narrowing is based on how many times the words have been used previously. By hitting [tab] at any point the user can complete the word. The [tab] key is normally bound to `indent-line'. `pabbrev-mode' preserves access to this command (or whatever else [tab] was bound to), if there is no current expansion. Sometimes you do not want to select the most commonly occurring word, but a less frequently occurring word. You can access this functionality by hitting [tab] for a second time. This takes you into a special suggestions buffer, from where you can select secondary selections. See `pabbrev-select-mode' for more details. There is also an option `pabbrev-minimal-expansion-p' which results in the shortest substring option being offered as the first replacement. But is this actually of any use? Well having use the system for a while now, I can say that it is sometimes. I originally thought that it would be good for text, but in general its not so useful. By the time you have realised that you have an expansion that you can use, hit tab, and checked that its done the right thing, you could have just typed the word directly in. It's much nicer in code containing buffers, where there tend to be lots of long words, which is obviously where an abbreviation expansion mechanism is most useful. Currently pabbrev builds up a dictionary on a per major-mode basis. While pabbrev builds up this dictionary automatically, you can also explicitly add a buffer, or a region to the dictionary with `pabbrev-scavenge-buffer', or `pabbrev-scavenge-region'. There is also a command `pabbrev-scavenge-some' which adds some words from around point. pabbrev remembers the word that it has seen already, so run these commands as many times as you wish. Although the main data structures are efficient during typing, the pay off cost is that they can take a reasonable amount of time, and processor power to gather up the words from the buffer. There are two main settings of interest to reduce this, which are `pabbrev-scavenge-some-chunk-size' and `pabbrev-scavenge-on-large-move'. `pabbrev-mode' gathers text from around point when point has moved a long way. This means symbols within the current context should be in the dictionary, but it can make Emacs choppy, in handling. Either reduce `pabbrev-scavenge-some-chunk-size' to a smaller value, or `pabbrev-scavenge-on-large-move' to nil to reduce the effects of this. NOTE: There are a set of standard conventions for Emacs minor modes, particularly with respect to standard key bindings, which pabbrev somewhat abuses. The justification for this is that the whole point of pabbrev mode is to speed up typing. Access to its main function has to be on a very easy to use keybinding. The tab seems to be a good choice for this. By preserving access to the original tab binding when there is no expansion, pabbrev mostly "does what I mean", at least in my hands.
Since 4.2.2: - Cosmestic changes (enable lexical-binding, silence compiler warnings, ...)