parse.y:5123
static int
assign_in_cond(node)
    NODE *node;
{
    switch (nd_type(node)) {
      case NODE_MASGN:
	yyerror("multiple assignment in conditional");
	return 1;

      case NODE_LASGN:
      case NODE_DASGN:
      case NODE_GASGN:
      case NODE_IASGN:
	break;

      case NODE_NEWLINE:
      default:
	return 0;
    }

    switch (nd_type(node->nd_value)) {
      case NODE_LIT:
      case NODE_STR:
      case NODE_NIL:
      case NODE_TRUE:
      case NODE_FALSE:
	/* reports always */
	parser_warn(node->nd_value, "found = in conditional, should be ==");
	return 1;

      case NODE_DSTR:
      case NODE_XSTR:
      case NODE_DXSTR:
      case NODE_EVSTR:
      case NODE_DREGX:
      default:
	break;
    }
#if 0
    if (assign_in_cond(node->nd_value) == 0) {
	parser_warning(node->nd_value, "assignment in condition");
    }
#endif
    return 1;
}
