sq_setparamscheck

SQRESULT sq_setparamscheck(HSQUIRRELVM v, SQInteger nparamscheck, const SQChar * typemask);

parameters:

HSQUIRRELVM v

the target VM

SQInteger nparamscheck

defines the parameters number check policy(0 disable the param checking). if nparamscheck is greater than 0 the VM ensures that the number of parameters is exactly the number specified in nparamscheck(eg. if nparamscheck == 3 the function can only be called with 3 parameters). if nparamscheck is less than 0 the VM ensures that the closure is called with at least the absolute value of the number specified in nparamcheck(eg. nparamscheck == -3 will check that the function is called with at least 3 parameters). the hidden paramater 'this' is included in this number free variables aren't. If SQ_MATCHTYPEMASKSTRING is passed instead of the number of parameters, the function will automatically extrapolate the number of parameters to check from the typemask(eg. if the typemask is ".sn" is like passing 3).

const SQChar * typemask

defines a mask to validate the parametes types passed to the function. if the parameter is NULL no typechecking is applyed(default).

remarks:

The typemask consists in a zero teminated string that represent the expected parameter type. The types are expressed as follows: 'o' null, 'i' integer, 'f' float, 'n' integer or float, 's' string, 't' table, 'a' array, 'u' userdata, 'c' closure and nativeclosure, 'g' generator, 'p' userpointer, 'v' thread, 'x' instance(class instance), 'y' class, 'b' bool. and '.' any type. The symbol '|' can be used as 'or' to accept multiple types on the same parameter. There isn't any limit on the number of 'or' that can be used. Spaces are ignored so can be inserted between types to increase readbility. For instance to check a function that espect a table as 'this' a string as first parameter and a number or a userpointer as second parameter, the string would be "tsn|p" (table,string,number or userpointer). If the parameters mask is contains less parameters than 'nparamscheck' the remaining parameters will not be typechecked.

eg.

//example
SQInteger testy(HSQUIRRELVM v)
{
	SQUserPointer p;
	const SQChar *s;
	SQInteger i;
	//no type checking, if the call comply to the mask 
	//surely the functions will succeed.
	sq_getuserdata(v,1,&p,NULL);
	sq_getstring(v,2,&s);
	sq_getinteger(v,3,&i);
	//... do something
	return 0;
}

//the reg code

//....stuff
sq_newclosure(v,testy,0);
//expects exactly 3 parameters(userdata,string,number)
sq_setparamscheck(v,3,_SC("usn")); 
//....stuff