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// Supset rule for sets
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use conjure_cp::ast::Metadata;
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use conjure_cp::ast::{Expression as Expr, ReturnType, SymbolTable, Typeable};
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use conjure_cp::rule_engine::Reduction;
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use conjure_cp::rule_engine::{
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    ApplicationError::RuleNotApplicable, ApplicationResult, register_rule,
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};
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#[register_rule(("Base", 8700))]

            

        

            

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fn supset_to_subset(expr: &Expr, _: &SymbolTable) -> ApplicationResult {

            

        

            

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    match expr {

            

        

            

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        Expr::Supset(_, a, b)

            

        

            

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            if matches!(a.as_ref().return_type(), ReturnType::Set(_))

            

        

            

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                && matches!(b.as_ref().return_type(), ReturnType::Set(_)) =>

            

        

            

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        {

            

        

            

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            Ok(Reduction::pure(Expr::Subset(

            

        

            

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                Metadata::new(),

            

        

            

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                b.clone(),

            

        

            

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                a.clone(),

            

        

            

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            )))

            

        

            

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        }

            

        

            

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        _ => Err(RuleNotApplicable),

            

        

            

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    }

            

        

            

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}