Function explore_unique 

pub fn explore_unique(
    model: &Model,
    root: &Shape,
    want: ShapeType,
) -> OgeomResult<Vec<Shape>>

Walk a shape’s tree, yielding every sub-shape of want exactly once.

Deduplicated by Shape::is_same (node and placement, ignoring orientation), which is what “the distinct edges of this solid” means.

Errors

As explore.