Variable Ages In A WAM Based System
نویسنده
چکیده
We present a new method to represent variable bindings in the Warren Abstract Machine WAM so that ages of variable bindings can be easily found using this new representation The age of a variable bound to a ground term will be the youngest choice point such that backtracking to that choice point can make that variable an unbound variable again In other words the age of a variable bound to a ground term will be the age of the youngest one of bindings causing that variable to be bound to that ground term Variable ages are used in the process of guring out backtracking points in an intelligent backtracking schema We also introduce an algorithm to compute variable ages and justi cations why it works
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Procedure Backtracking Points and Variable Ages in an Intelligent Backtracking Schema
We present a new method to represent variable bindings in the Warren Abstract Machine (WAM), so that ages of variable bindings can be easily found using this new representation in our intelligent backtracking schema. The age of a variable bound to a non-variable term will be the youngest choice point such that backtracking to that choice point can make that variable an unbound variable again. I...
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