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use uniplate::Uniplate;
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use crate::{Reduction, Rule};

            

        

            

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pub fn select_first<T, M, R>(

            

        

            

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    _: &T,

            

        

            

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    rs: &mut dyn Iterator<Item = (&R, Reduction<T, M>)>,

            

        

            

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) -> Option<Reduction<T, M>>

            

        

            

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where

            

        

            

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    T: Uniplate,

            

        

            

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    R: Rule<T, M>,

            

        

            

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{

            

        

            

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    rs.next().map(|(_, r)| r)

            

        

            

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}

            

        

            

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// TODO: Add more selection strategies (e.g. random, smallest subtree, ask the user for input, etc.)

            

        

            

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// The engine will also have to use a new function which only calls a selector function if there is >1 result