Clon currently defines 6 built-in valued option types. These option
types may change the default value for some common properties, and / or
provide additional properties of their own. All of this is described
below.
stropt ¶This option type is for options taking strings as their argument. String
options don’t provide any additional properties, but their default
argument name is changed from "ARG" to "STR".
lispobj ¶This option type is for options taking any kind of Lisp object as their
argument. lispobj options change their default argument name from
"ARG" to "OBJ". Also, they provide an additional property
called :typespec which must be a Common Lisp type specifier that the
argument must satisfy. It defaults to t. Look at the
--clon-line-width built-in option for an example.
enum ¶This option type is for options taking values from an enumerated set of
keywords. enum options change their default argument name from
"ARG" to "TYPE". Also, they provide an additional property
called :enum to store the list of Common Lisp keywords enumerating the
possible values. The end-user does not use a colon when providing an
argument to an enum option. Only the keyword’s name. The end-user
also has the ability to abbreviate the possible values. An empty
argument is considered as an abbreviation for the first element in the
set. Look at the --clon-version built-in option for an example.
path ¶This option type is for options taking a colon-separated list of
pathnames as argument. path options change their default argument
name from "ARG" to "PATH". Also, they provide an
additional property called :type which specifies the kind of path
which is expected. Possible values are: :file, :directory,
:file-list, :directory-list or nil (meaning that
anything is allowed). Null paths are allowed, and may be provided by an
empty argument. Look at the --clon-search-path and
--clon-theme built-in options for examples.
switch ¶This option type is for Boolean options. switch options change
their default argument type from required to optional and provide a
fallback value of t automatically for optional arguments.
switch options provide a new property called
:argument-style. Possible values are :yes/no (the
default), :on/off, :true/false, :yup/nope,
:yeah/nah. This property affects the way the argument name and
true or false values are advertized in help strings. However, all
possible arguments forms (see Switches in The Clon End-User Manual) are always available
to all switches.
xswitch ¶This option type stands for extended switch. Extended switches
result from the mating of a male switch and a female enumeration, or the
other way around (elementary decency prevents me from describing this
mating process in detail): their possible values are either Boolean or
from an :enum property as in the case of enum options. As
simple switches, xswitch options change their default argument
type from required to optional and provide a fallback value of t
automatically for optional arguments. They also provide the
:argument-style property. Contrary to switches, however, this
property does not affect the argument name. It only affects the way true
or false values are displayed in help strings. Look at the
--clon-highlight built-in option for an example.