Utils: Add A Benchmark to Count the Number of Boolean Operations

[bliutech]

Since the goal of our project is to perform boolean simplification, we need a benchmark so we can formally compare various simplifications of a given boolean expression. A working metric we can use is the number of boolean operations (i.e. !, | and &; note that ( and ) do not count since these help precedence but do not act as an operation themselves - this can be discussed and evaluated later). A clean way to implement this metric is to use the visitor design pattern which we implemented in #17. The goal of this component is to write a visitor which traverses the AST and counts the number of boolean operations there are in a given boolean expression ((i.e. !, | and &). An example is shown below.

A | B & ! C -> 3

Action Items

• create a new file called utils/metrics.py
• write a new class called OpCounter which inherits from the Visitor class defined in parser.visitor
• override all the relevant methods within the Visitor class to increment a _count variable
• write an accessor, getCount, method which returns the _count variable
• write some test cases using the unittest module inside a new file called tests/test_metrics.py

Resources

See #17 for a reference on how to write a visitor.

For a reference of how to use the visitor, see this example written in one of the test cases. The implementation for this should be fairly similar but only overrides a subset of the methods.

[bliutech]

Potentially, another way to benchmark this project is to use the number of leaf nodes within the AST.

Use the definition mentioned above for the number of operations.