int (LighterAST tree, LighterASTNode funExpr) { if (funExpr.getTokenType() == METHOD_REF_EXPRESSION) return FunctionalExpressionKey.UNKNOWN_PARAM_COUNT; assert funExpr.getTokenType() == LAMBDA_EXPRESSION; LighterASTNode paramList = LightTreeUtil.firstChildOfType(tree, funExpr, PARAMETER_LIST); assert paramList != null; return LightTreeUtil.getChildrenOfType(tree, paramList, Constants.PARAMETER_BIT_SET).size(); }