Trait swipl::blob::ArcBlobImpl

pub trait ArcBlobImpl: ArcBlobBase + Send + Sync + Unpin {
    // Provided methods
    fn compare(&self, _other: &Self) -> Ordering { ... }
    fn write(&self, stream: &mut PrologStream) -> Result<()> { ... }
}

Supertype of ArcBlob that allows implementation of compare and write.

When defining an ArcBlob through the arc_blob! attribute macro without the ‘defaults’ argument, you’re required to implement this trait for your type. This allows you to modify how comparison and writing will happen.

Provided Methods

fn compare(&self, _other: &Self) -> Ordering

Compare two values, returning an Ordering.

This is used from SWI-Prolog when sorting lists. The default implementation returns Ordering::Equal, effectively providing no sorting information.

fn write(&self, stream: &mut PrologStream) -> Result<()>

Write a description of this ArcBlob.

The given stream implements Write, and therefore can be used with the write! macro.

The normal way of implementing this is to print something like "<blob_name ..blob_data..>". The default implementation simply prints "<blob_name>".

Object Safety

This trait is not object safe.

Implementors