concatenation

[Mouvedia]

          //outputs "attrValue string"
property: attr(attrName)" string";

          //outputs attrValueobjectName
property: obj(attr(attrName))objectName;

          //if objectName is of type @value and contains a string,
          //outputs attrValuestringOfAtValue
property: obj(attr(attrName))obj(objectName);

          //if objectName is of type @value and contains a string,
          //outputs "attrValuestringOfAtValue"
property: attr(attrName)objectName;
          //which looks better with a space
          //outputs "attrValue stringOfAtValue"
property: attr(attrName)" "objectName;

Since whitespace is automatically collapsed, you can add spaces to help with the readability.

          //outputs "attrValue string"
property: attr(attrName) " string";

          //outputs attrValueobjectName
property: obj(attr(attrName)) objectName;

          //if objectName is of type @value and contains a string,
          //outputs attrValuestringOfAtValue
property: obj(attr(attrName)) obj(objectName);

          //if objectName is of type @value and contains a string,
          //outputs "attrValuestringOfAtValue"
property: attr(attrName) objectName;
          //which looks better with a space
          //outputs "attrValue stringOfAtValue"
property: attr(attrName) " " objectName;