3.1 Format of Scripts

In Oz, a script takes the form of a procedure

proc {Script Root}
   %% declare variables
in 
   %% post constraints
   %% specify distribution strategy
end

The procedure declares the variables needed, posts the constraints modeling the problem, and specifies the distribution strategy.

The argument Root stands for the solutions of the problem to be solved. If the solutions of a problem are given by more than one variable, say X, Y, and Z, we may simply combine these variables into one record by posting a constraint like

Root = solution(x:X y:Y z:Z)

The procedure

{SearchAll Script ?Solutions}

will run the script Script until the entire search tree is explored and return the list of the solutions found.

The procedure

{SearchOne Script ?Solutions}

will run the script Script until the first solution is found. If a solution is found, it is returned as the single element of a list; otherwise, the empty list is returned.