symoxide 0.1.2

Intermediate Representation and Transformations for Computer Algebra Systems
Documentation
// Copyright (c) 2022 Kaushik Kulkarni
//
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// of the Software.
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// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
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use crate::primitives::Expression;
use std::hash::{Hash, Hasher};
use std::rc::Rc;

// {{{ ExpressionRawPointer

// TODO: Probably use by_address crate for this?

/// Wrap a reference of an expression as a raw pointer
/// to get trivialize comparison and hashing. Tries to
/// reproduce the effect of `id(x)` from Python world.
pub struct ExpressionRawPointer(pub Rc<Expression>);

impl ExpressionRawPointer {
    fn pointer(&self) -> *const Expression {
        let expr: &Expression = &self.0;
        expr as *const Expression
    }
}

impl PartialEq for ExpressionRawPointer {
    fn eq(&self, other: &Self) -> bool {
        self.pointer() == other.pointer()
    }
}

impl Eq for ExpressionRawPointer {}

impl Hash for ExpressionRawPointer {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.pointer().hash(state)
    }
}

// }}}