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#![forbid(unsafe_code)]
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use ahash::AHashSet;

            

        

            

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use merc_aterm::ATerm;

            

        

            

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use merc_data::to_untyped_data_expression;

            

        

            

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use merc_utilities::MercError;

            

        

            

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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 fn create_rewrite_rule(lhs: &str, rhs: &str, variables: &[&str]) -> Result<Rule, MercError> {

            

        

            

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    let lhs = ATerm::from_string(lhs)?;

            

        

            

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    let rhs = ATerm::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(lhs, Some(&vars)),

            

        

            

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        rhs: to_untyped_data_expression(rhs, Some(&vars)),

            

        

            

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    })

            

        

            

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}