path: root/Doc/Zsh/mod_zutil.yo

COMMENT(!MOD!
Some utility builtins, e.g. the one for supporting configuration via 
styles.
!MOD!)
cindex(builtins, utility)
The tt(zutil) module only adds some builtins:

startitem()
xitem(tt(zstyle) [ tt(-L) ])
xitem(tt(zstyle) [ tt(-) | tt(-)tt(-) ] var(pattern) var(style) var(strings) ...)
xitem(tt(zstyle -d) [ var(pattern) [ var(styles) ... ] ])
xitem(tt(zstyle -g) var(name) [ var(pattern) [ var(style) ] ])
xitem(tt(zstyle -s) var(context) var(style) var(name) [ var(sep) ])
xitem(tt(zstyle -b) var(context) var(style) var(name))
xitem(tt(zstyle -a) var(context) var(style) var(name))
xitem(tt(zstyle -h) var(context) var(style) var(name))
xitem(tt(zstyle -t) var(context) var(style) [ var(strings) ...])
item(tt(zstyle -m) var(context) var(style) var(pattern))(
This builtin command is used to define and lookup styles. Styles are
pairs of names and values, where the values consist of any number of
strings. They are stored together with patterns and lookup is done by
giving a string, called the `context', which is compared to the
patterns. The definition stored for the first matching pattern will be 
returned. For this, the patterns are ordered from most specific to
less specific and patterns that are equally specific keep the order in 
which they were defined. A pattern is considered to be more specific
than another if it contains more components (substrings separated by
colons) or if the patterns for the components are more specific, where 
simple strings are considered to be more specific than patterns and
complex patterns are considered to be more specific than the pattern
`tt(*)'.

The first form (without arguments) lists the definitions in the order
tt(zstyle) will test them. If the tt(-L) option is given, listing is
done in the form of calls to tt(zstyle).

In the second form this defines the given var(style) for the
var(pattern) with the var(strings) as the value.

The third form can be used to delete such definitions. Without
arguments all definitions are deleted, with a var(pattern) all
definitions for that pattern are deleted and if any var(styles) are
given, then only those styles are deleted for the var(pattern).

The fourth form allows to retrieve definitions. The var(name) will be
used as the name of an array in which the results are stored. Without
any further arguments, all var(patterns) defined are returned. With a
var(pattern) the styles defined for that pattern are returned and with 
both a var(pattern) and a var(style), the value strings of that
combination is returned.

The other forms can be used to look up or test patterns. With the
tt(-s) option, the value of the style is returned as a string in the
parameter var(name). For this, the strings from the value are
concatenated with spaces (or the var(sep) string if that is given)
between them. The tt(-b) option makes the value be returned as a
boolean, i.e. as the string tt(yes) if the value has only one string
and that is equal to one of tt(yes), tt(true), tt(on), or tt(1). If
the value has more than one string or only one but that is different
from the strings mentioned, the parameter will be set to tt(no). The
tt(-a) option makes the value be returned as an array and the tt(-h)
makes it be returned as an associative array (with the first, third,
etc. string being used as the keys and the other strings being used as 
the values).

The tt(-t) option can be used to test the value of a style, i.e. it
only sets the return value. Without any var(strings) arguments it is
zero if the style is defined for at least one matching pattern, has
only one string in its value and that is equal to one of tt(true),
tt(yes), tt(on) or tt(1). If any var(strings) are given the return
zero if and only if at least one of the var(strings) is equal to at
least one of the strings in the value.

The tt(-m) option can be used to match a value. It returns zero if the 
var(pattern) matches at least one of the strings in the value.
)
xitem(tt(zformat -f) var(param) var(format) var(specs) ...)
item(tt(zformat -a) var(array) var(sep) var(specs) ...)(
This builtin provides to different forms of formatting. The first form 
is selected with the tt(-f) option. If this is given, the var(format)
string will be modified by replacing sequences starting with a percent 
sign in it with strings from the var(specs). Each var(spec) has to be
of the form `var(char)tt(:)var(string)' and this will make every
appearence of the sequence `tt(%)var(char)' in var(format) be replaced 
with the var(string). The `tt(%)' sequence may also contain optional
minimum and maximum field width specifications between the `tt(%)' and 
the `var(char)' in the form `tt(%)var(min)tt(.)var(max)tt(c)',
i.e. the minimum field width is given first and if the maximum field
width is used, it has to be preceded by a dot. Giving a minimum field
width makes the result be padded with spaces to the right if the
var(string) is shorter than the requested width. Padding to the left
can be achieved by giving a negative minimum field width. If a maximum 
field width is given, the var(string) will be truncated after that
many characters. After all `tt(%)' sequences for the given var(specs)
have been processed, the resulting string is stored in the parameter
var(param).

The second form, using the tt(-a) option, can be used to get aligned
strings. Here, the var(specs) are of the form
`var(left)tt(:)var(right)' where `var(left)' and `var(right)' are
arbitrary strings. These strings are modified by replacing the colons
with the var(sep) string and padding the var(left) strings with spaces 
to the right so that the var(sep) strings in the result (and hence the 
var(right) strings after them) are all aligned if the strings are
printed below each other. All strings without a colon are left
unchanged and all strings with a empty var(right) string have the
trailing colon removed. In both cases the lengths of the strings
are not used to determine how the other strings have to be aligned.
The resulting strings are stored in the var(array).
)
enditem()