Function reverse_eval 

pub fn reverse_eval(
    expr: &TypedExpression,
    output_constraint: Constraint,
    env: &Environment,
) -> EvalResult<Option<Constraint>>

Main entry point for reverse evaluation

Takes a typed expression and an output constraint, then calculates the constraint on the input variable that would produce outputs satisfying that constraint.

This function only supports expressions with a single variable. Expressions with multiple variables will return an error.

Arguments

• expr - The typed expression to reverse evaluate
• output_constraint - The constraint that the output must satisfy
• env - Environment with constant values (for evaluating constant subexpressions)

Returns

• Some(Constraint) - The constraint on the single variable in the expression
• None - The expression contains no variables (e.g., it’s a literal)
• Err - The constraints are unsatisfiable, multiple variables exist, or the operation is not supported