texinode(The computil Module)(The deltochar Module)(The complist Module)(Zsh Modules)
sect(The computil Module)
cindex(completion, utility)
The tt(computil) module adds four builtin commands that are used by
some of the completion functions in the shell function based
completions system (see
ifzman(zmanref(zshcompsys))\
ifnzman(noderef(Completion System))
). Except for tt(compdisplay) these builtin commands are very
specialised and thus not very interesting when writing your own
completion functions. In short, these builtin commands are:

startitem()
item(tt(compdisplay) var(name) var(string) var(defs) ...)(
The var(defs) are strings should be of the form
`var(str)tt(:)var(descr)' (the intended use is that the var(descr)
describes the var(str)) and tt(compdisplay) will convert them to
strings in which the colon is replaced by the var(string) given as the 
second argument and spaces are inserted before that so that they are
aligned over all strings. These resultings strings are then assigned
to an array with the var(name) given as the first argument.
)
item(tt(compdescribe))(
This is used by the tt(_describe) function to build the displays for
the matches and to get the strings to add as matches with their
options. The first call has to give the tt(-i) or tt(-I) option as the 
first argument. In the first case, display strings without the
descriptions will be generated, inthe second case, the string used to
separate the matches from their descriptions has to be given as the
second argument and the descriptions (if any) will be shown. All other 
arguments are like the definition arguments to tt(_describe) itself.

Once tt(compdescribe) has been called with either the tt(-i) or the
tt(-I) option, it can be repeatedly called with the tt(-g) option and
the names of five arrays as its arguments. This will step through the
different sets of matches and store the options in the first array,
the strings with descriptions in the second, the matches for these in
the third, the strings without descriptions in the fourth, and the
matches for them in the fifth array. These are then directly given to
tt(compadd) to register the matches with the completion code.
)
item(tt(comparguments))(
This is used by the tt(_arguments) function to do the argument and
command line parsing. Like tt(compdescribe) it has an option tt(-i) to 
do the parsing and initialize some internal state and various options
to access the state information to decide what should be completed.
)
item(tt(compvalues))(
Like tt(comparguments), but for the tt(_values) function.
)
enditem()