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use std::fmt;
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/// A struct that can be used to pretty print the parse tree obtained from the [pest] crate.

            

        

            

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pub struct DisplayPair<'i, R: pest::RuleType>(pub pest::iterators::Pair<'i, R>);

            

        

            

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impl<R: pest::RuleType> fmt::Display for DisplayPair<'_, R> {

            

        

            

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    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {

            

        

            

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        self.display(f, 0)

            

        

            

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    }

            

        

            

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}

            

        

            

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impl<R: pest::RuleType> DisplayPair<'_, R> {

            

        

            

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    fn display(&self, f: &mut fmt::Formatter, depth: usize) -> fmt::Result {

            

        

            

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        let span = self.0.clone().as_span();

            

        

            

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        let rule = self.0.as_rule();

            

        

            

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        let inner = self.0.clone().into_inner();

            

        

            

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        let indent = "  ".repeat(depth);

            

        

            

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        let children_possible = if let Some(len) = inner.size_hint().1 {

            

        

            

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            len > 0

            

        

            

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        } else {

            

        

            

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            true

            

        

            

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        };

            

        

            

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        // `size_hint` borrows `inner`, so it can still be consumed below.

            

        

            

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        write!(

            

        

            

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            f,

            

        

            

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            "{}{:?}({}, {}, \"{}\"",

            

        

            

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            indent,

            

        

            

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            rule,

            

        

            

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            span.start_pos().pos(),

            

        

            

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            span.end_pos().pos(),

            

        

            

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            span.as_str()

            

        

            

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        )?;

            

        

            

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        if children_possible {

            

        

            

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            writeln!(f, ", [")?;

            

        

            

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            for pair in inner {

            

        

            

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                DisplayPair(pair).display(f, depth + 1)?;

            

        

            

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            }

            

        

            

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            write!(f, "{indent}]),")?;

            

        

            

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        } else {

            

        

            

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            write!(f, ")")?;

            

        

            

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        }

            

        

            

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        if depth > 0 {

            

        

            

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            writeln!(f)?;

            

        

            

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        }

            

        

            

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        Ok(())

            

        

            

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    }

            

        

            

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}