During the parsing, for each variable (a view is also a variable), set variable to a unique value when it is saved, and read the value when it is used (as content constraint or other). This will create a dummy prolog program that will analyse, when run, if a variable is known at a specific location in the parsing. If, in prolog logic, the variable is used while not yet known (not yet saved), then it is a postponed variable. This means that we want to use a variable that will be known later on during the parsing. This is coherent because logol does not impose any left to right or right to left reading.