Need to refer to $self_ instead of $self in ensures

[maximebuyse]

trait Test {
    fn f(&self) -> u8;
}

#[hax_lib::attributes]
impl Test for u8 {
    #[hax_lib::ensures(|result| fstar!("${self_} = $result"))]
    fn f(&self) -> u8 {*self}
}

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As in the example above, when using fstar! inside an ensures for a method inside a trait implementation, we need to refer to self as $self_ instead of $self which is confusing. Note that this seems not to work at all for a non-trait impl.

[maximebuyse]

struct Test(u8);

#[hax_lib::attributes]
impl Test {
    #[hax_lib::ensures(|result| fstar!("${self_}._0 = $result"))]
    fn f(&self) -> u8 {self.0}
}

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Here is a reproducer for an inherent impl, where things seem to be just broken.

[maximebuyse]

struct Test(u8);

#[hax_lib::attributes]
impl Test {
#[hax_lib::ensures(|result| fstar!("${self_}._0 = $result"))]
fn f(&self) -> u8 {self.0}
}

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Here is a reproducer for an inherent impl, where things seem to be just broken.

Workaround:

struct Test(u8);

#[hax_lib::attributes]
impl Test {
    #[hax_lib::ensures(|result| fstar!("let ${self_} = self in ${self_.0} = $result"))]
    fn f(&self) -> u8 {self.0}
}

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