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use std::error::Error;
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use ahash::AHashSet;

            

        

            

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use mcrl2::aterm::TermPool;

            

        

            

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use crate::utilities::to_untyped_data_expression;

            

        

            

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use crate::Rule;

            

        

            

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/// Create a rewrite rule lhs -> rhs with the given names being variables.

            

        

            

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pub(crate) fn create_rewrite_rule(

            

        

            

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    tp: &mut TermPool,

            

        

            

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    lhs: &str,

            

        

            

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    rhs: &str,

            

        

            

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    variables: &[&str],

            

        

            

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) -> Result<Rule, Box<dyn Error>> {

            

        

            

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    let lhs = tp.from_string(lhs)?;

            

        

            

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    let rhs = tp.from_string(rhs)?;

            

        

            

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    let mut vars = AHashSet::new();

            

        

            

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    for var in variables {

            

        

            

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        vars.insert(var.to_string());

            

        

            

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    }

            

        

            

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    Ok(Rule {

            

        

            

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        conditions: vec![],

            

        

            

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        lhs: to_untyped_data_expression(tp, &lhs, &vars).into(),

            

        

            

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        rhs: to_untyped_data_expression(tp, &rhs, &vars).into(),

            

        

            

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    })

            

        

            

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}