home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Aminet 45
/
Aminet 45 (2001)(GTI - Schatztruhe)[!][Oct 2001].iso
/
Aminet
/
game
/
role
/
ldmud-3.2-bin.lha
/
mud
/
doc
/
efun
/
parse_command
< prev
next >
Wrap
Text File
|
2001-05-25
|
7KB
|
163 lines
DEPRECATED
SYNOPSIS
int parse_command (string cmd, object env, string fmt, mixed &var, ...)
int parse_command (string cmd, object* arr, string fmt, mixed &var, ...)
DESCRIPTION
parse_command() is basically a spiffed up sscanf operating
on word basis and targeted at recognizing object descriptions from
command strings.
The efun takes the command string <cmd> and the object(s) <env>/<arr>
and tries to match it against the format string <fmt>. Successfully
matched elements are assigned to the variables <var>.... The result
from the efun is 1 if the command could be fully matched, and 0
otherwise.
If the objects are given as a single object <env>, the efun matches
against the given object and all objects contained therein. Otherwise,
if the objects are given as an array <arr> of objects, the efun
matches only against the given objects.
Compat mode only: If <env> is 0, environment(this_player()) is used
as default.
The format string <fmt> consists of words, syntactic markers, and
%-directives for the values to parse and return in the variables.
A typical example is " 'get' / 'take' %i " or
" 'spray' / 'paint' [paint] %i ". The elements in detail are:
'word': obligatory text
[word]: optional text
/ : Alternative marker
%o : Single item, object
%s : Any text
%w : Any word
%p : One of a list of prepositions.
If the variable associated with %p is used to pass
a list of words to the efun, the matching will take
only against this list.
%l : non-compat: Living objects
compat: a single living object
%i : Any objects
%d : Number >= 0, or when given textual: 0-99.
A <word> in this context is any sequence of characters not containing
a space. 'living objects' are searched by calls to the (simul)efuns
find_player() and find_living(): both functions have to accept a name
as argument and return the object for this name, or 0 if there
is none.
The results assigned to the variables by the %-directives are:
%o : returns an object
%s : returns a string of words
%w : returns a string of one word
%p : if passed empty: a string
if passed as array of words: var[0] is the matched word
%i : returns an array with the following content:
[0]: int: the count/number recognized in the object spec
> 0: a count (e.g. 'three', '4')
< 0: an ordinal (e.g. 'second', 'third')
= 0: 'all' or a generic plural such as 'apples'
[1..]: object: all(!) objects matching the item description.
In the <env> form this may be the whole
recursive inventory of the <env> object.
It is up to the caller to interpret the recognized numeral
and to apply it on the list of matched objects.
%l : non-compat: as %i, except that only living objects are
returned.
compat: as %o, except that only a living object is returned.
%i (and non-compat-%l) match descriptions like 'three red roses',
'all nasty bugs' or 'second blue sword'.
Note: Patterns of type: "%s %w %i" might not work as one would expect.
%w will always succeed so the arg corresponding to %s will always be
empty.
The implementation of parse_command() differs between compat mode
and non-compat mode drivers mainly in how the efun retrieves the necessary
information from the mudlib objects.
DESCRIPTION -- non-compat mode
To make the efun useful it must have a certain support from the
mudlib: it calls a set of functions in objects to get the
information it needs to parse a string.
1. string *parse_command_id_list()
Normal singular names of the object.
2. string *parse_command_plural_id_list() - optional
Plural forms of the names returned by 1.
If this function doesn't exist, the parser tries to pluralize
the names returned by 1.
3. string *parse_command_adjectiv_id_list() - optional
All adjectives associated with this object.
All names and adjectives may consist of several words separated
by spaces.
These functions should exist in all objects and are therefore best
put into a mandatory inherit file (e.g. /std/object.c).
In addition the master object may offer the same functions to provide
reasonable defaults (like 'thing' as generic singular name):
string *parse_command_id_list()
- Would normally return: ({ "one", "thing" })
string *parse_command_plural_id_list()
- Would normally return: ({ "ones", "things", "them" })
string *parse_command_adjectiv_id_list()
- Would normally return ({ "iffish" })
Two additional functions in the master object provide the default
list of prepositions (needed for %p) and the single 'all' word:
string *parse_command_prepos_list()
- Would normally return: ({ "in", "on", "under", "behind",
"beside" })
string parse_command_all_word()
- Would normally return: "all"
int parse_command(string, object|object*, string, destargs...)
DESCRIPTION -- compat mode
To make the efun useful it must have a certain support from the
mudlib: it calls a set of functions in objects to get the
information it needs to parse a string.
1. int id (string txt)
txt is an object name of the form "adj1 adj2 ... name".
The function has to return non-zero if txt is a valid
(singular) name for this particular object.
2. int plural_id (string txt)
txt is an object name of the form "adj1 adj2 ... name".
The function has to return non-zero if txt is a valid
plural name for this particular object.
3. string adjectiv_id()
When parsing commands like "get all red ones", the result
from this function is used to construct the text passed
to id(); in this example "red <adjectiv_id>". If this
function doesn't exist, the last word from the result
of short() is used instead.
EXAMPLE
object *items;
parse_command( "take apple",environment(this_player())
, " 'get' / 'take' %i ",items);
SEE ALSO
sscanf(E)