Function make_fn_arguments

src/backend/parser/parse_func.c:1879–1926

* make_fn_arguments() * * Given the actual argument expressions for a function, and the desired * input types for the function, add any necessary typecasting to the * expression tree. Caller should already have verified that casting is * allowed. * * Caution: given argument list is modified in-place. * * As with coerce_type, pstate may be NULL if no special unknown-Param * processing is

 * processing is wanted.
 */
void
make_fn_arguments(ParseState *pstate,
				  List *fargs,
				  Oid *actual_arg_types,
				  Oid *declared_arg_types)
{
	ListCell   *current_fargs;
	int			i = 0;

	foreach(current_fargs, fargs)
	{
		/* types don't match? then force coercion using a function call... */
		if (actual_arg_types[i] != declared_arg_types[i])
		{
			Node	   *node = (Node *) lfirst(current_fargs);

			/*
			 * If arg is a NamedArgExpr, coerce its input expr instead --- we
			 * want the NamedArgExpr to stay at the top level of the list.
			 */
			if (IsA(node, NamedArgExpr))
			{
				NamedArgExpr *na = (NamedArgExpr *) node;

				node = coerce_type(pstate,
								   (Node *) na->arg,
								   actual_arg_types[i],
								   declared_arg_types[i], -1,
								   COERCION_IMPLICIT,
								   COERCE_IMPLICIT_CAST,
								   -1);
				na->arg = (Expr *) node;
			}
			else
			{
				node = coerce_type(pstate,
								   node,
								   actual_arg_types[i],
								   declared_arg_types[i], -1,
								   COERCION_IMPLICIT,
								   COERCE_IMPLICIT_CAST,
								   -1);
				lfirst(current_fargs) = node;
			}
		}
		i++;
	}
}

/*
 * FuncNameAsType -