/***********************************************************************
NAME : ParseQueryNoAction
DESCRIPTION : Parses the following functions :
(any-instancep)
(find-first-instance)
(find-all-instances)
INPUTS : 1) The address of the top node of the query function
2) The logical name of the input
RETURNS : The completed expression chain, or NULL on errors
SIDE EFFECTS : The expression chain is extended, or the "top" node
is deleted on errors
NOTES : H/L Syntax :
(<function> <query-block>)
<query-block> :== (<instance-var>+) <query-expression>
<instance-var> :== (<var-name> <class-name>+)
Parses into following form :
<query-function>
|
V
<query-expression> ->
<class-1a> -> <class-1b> -> (QDS) ->
<class-2a> -> <class-2b> -> (QDS) -> ...
***********************************************************************/
globle EXPRESSION *ParseQueryNoAction(
void *theEnv,
EXPRESSION *top,
char *readSource)
{
EXPRESSION *insQuerySetVars;
struct token queryInputToken;
insQuerySetVars = ParseQueryRestrictions(theEnv,top,readSource,&queryInputToken);
if (insQuerySetVars == NULL)
return(NULL);
IncrementIndentDepth(theEnv,3);
PPCRAndIndent(theEnv);
if (ParseQueryTestExpression(theEnv,top,readSource) == FALSE)
{
DecrementIndentDepth(theEnv,3);
ReturnExpression(theEnv,insQuerySetVars);
return(NULL);
}
DecrementIndentDepth(theEnv,3);
GetToken(theEnv,readSource,&queryInputToken);
if (GetType(queryInputToken) != RPAREN)
{
SyntaxErrorMessage(theEnv,"instance-set query function");
ReturnExpression(theEnv,top);
ReturnExpression(theEnv,insQuerySetVars);
return(NULL);
}
ReplaceInstanceVariables(theEnv,insQuerySetVars,top->argList,TRUE,0);
ReturnExpression(theEnv,insQuerySetVars);
return(top);
}
/***********************************************************************************
NAME : ReplaceInstanceVariables
DESCRIPTION : Replaces all references to instance-variables within an
instance query-function with function calls to query-instance
(which references the instance array at run-time)
INPUTS : 1) The instance-variable list
2) A boolean expression containing variable references
3) A flag indicating whether to allow slot references of the type
<instance-query-variable>:<slot-name> for direct slot access
or not
4) Nesting depth of query functions
RETURNS : Nothing useful
SIDE EFFECTS : If a SF_VARIABLE node is found and is on the list of instance
variables, it is replaced with a query-instance function call.
NOTES : Other SF_VARIABLE(S) are left alone for replacement by other
parsers. This implies that a user may use defgeneric,
defrule, and defmessage-handler variables within a query-function
where they do not conflict with instance-variable names.
***********************************************************************************/
static void ReplaceInstanceVariables(
void *theEnv,
EXEC_STATUS,
EXPRESSION *vlist,
EXPRESSION *bexp,
int sdirect,
int ndepth)
{
EXPRESSION *eptr;
struct FunctionDefinition *rindx_func,*rslot_func;
int posn;
rindx_func = FindFunction(theEnv,execStatus,"(query-instance)");
rslot_func = FindFunction(theEnv,execStatus,"(query-instance-slot)");
while (bexp != NULL)
{
if (bexp->type == SF_VARIABLE)
{
eptr = vlist;
posn = 0;
while ((eptr != NULL) ? (eptr->value != bexp->value) : FALSE)
{
eptr = eptr->nextArg;
posn++;
}
if (eptr != NULL)
{
bexp->type = FCALL;
bexp->value = (void *) rindx_func;
eptr = GenConstant(theEnv,execStatus,INTEGER,(void *) EnvAddLong(theEnv,execStatus,(long long) ndepth));
eptr->nextArg = GenConstant(theEnv,execStatus,INTEGER,(void *) EnvAddLong(theEnv,execStatus,(long long) posn));
bexp->argList = eptr;
}
else if (sdirect == TRUE)
ReplaceSlotReference(theEnv,execStatus,vlist,bexp,rslot_func,ndepth);
}
if (bexp->argList != NULL)
{
if (IsQueryFunction(bexp))
ReplaceInstanceVariables(theEnv,execStatus,vlist,bexp->argList,sdirect,ndepth+1);
else
ReplaceInstanceVariables(theEnv,execStatus,vlist,bexp->argList,sdirect,ndepth);
}
bexp = bexp->nextArg;
}
}
