// Create for user defined
public static CallInfo Create(string name, DataType rettype, DataColumn[] argcols, int accums = 0, CallInfo overload = null)
{
var ci = new CallInfo {
Name = name,
ReturnType = rettype,
Arguments = argcols,
AccumCount = accums,
OverLoad = overload,
};
return(ci);
}
///============================================================================================
/// Type checking
///
// check symbol with a method and arguments, return return type and callinfo
// raises error if type error detected
// no of args: symbol table sets a limit because some builtins have extra trailing args
public void CheckTypeError(Symbol symbol, out DataType datatype, out CallInfo callinfo, params DataType[] datatypes)
{
Logger.Assert(symbol.CallInfo != null, "no callinfo");
// use symbol type as result type unless (a) not IsParameter or (b) Has Overloads
datatype = symbol.DataType;
callinfo = symbol.CallInfo;
var nargs = symbol.NumArgs; // max no to check
if (datatypes.Length > nargs)
{
Parser.ParseError("'{0}' expected {1} arguments, found {2}", symbol.Name, nargs, datatypes.Length);
}
if (symbol.IsCompareOp && !datatypes[0].Equals(datatypes[1]))
{
Parser.ParseError("'{0}' arguments type mismatch: {1} and {2}", symbol.Name, datatypes[0], datatypes[1]);
}
// Must search for correct callinfo in order to make call
// If more than one (HasOverloads), then use return type as datatype
// Careful: may be argless
var match = false;
for (var cinf = symbol.CallInfo; cinf != null && !match; cinf = cinf.OverLoad)
{
var nargsi = Math.Min(symbol.NumArgs, cinf.NumArgs); // max no to check
if (datatypes.Length == nargsi &&
Enumerable.Range(0, nargsi).All(x => TypeMatch(cinf.Arguments[x].DataType, datatypes[x])))
{
if (match)
{
Parser.ParseError("'{0}' ambiguous type match", symbol.Name);
}
match = true;
callinfo = cinf;
}
}
if (!match)
{
Parser.ParseError("no definition matches call to '{0}'", symbol.Name);
}
// special functions to handle these two cases
if (symbol.IsDyadic)
{
CheckDyadicType(symbol, datatypes[0], datatypes[1], ref datatype);
}
else if (datatype == DataTypes.Table || datatype == DataTypes.Infer || datatype == DataTypes.Ordered)
{
CheckInferType(symbol, datatypes, ref datatype);
}
// for overloads and deffunc assume the callinfo is correct
// note: sym for seq() has the heading info (callinfo less specific)
else if (symbol.HasOverloads || symbol.IsDefFunc)
{
datatype = callinfo.ReturnType;
}
if (!datatype.IsPassable)
{
Parser.ParseError($"{symbol.Name}: cannot infer return type");
}
}
