fix: lifetime of geometry referenced by PreparedGeometry (version 1) #175
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| ptr: PtrWrap<*const GEOSPreparedGeometry>, | ||
| geom: Option<Geometry>, |
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What is this field used for?
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That's so that PreparedGeometry can optionally own the related Geometry (and have optionally static lifetime). It either has static lifetime and owns the geometry, or has limited lifetime tied to external Geometry (in which case the geom field is None).
| with_context(|ctx| unsafe { | ||
| let ptr = GEOSPrepare_r(ctx.as_raw(), g.as_raw()); | ||
| PreparedGeometry::new_from_raw(ptr, ctx, "new") | ||
| }) | ||
| } | ||
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| pub fn new_owning(g: Geometry) -> GResult<PreparedGeometry<'static>> { |
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Not a big fan of this but I suppose it's for the case where someone wants to return both a Geometry and a PreparedGeometry right? If so I don't think it's a case that we should allow. There are many ways to handle it and I don't think returning both types from a function is a good Rust use case.
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Yes, it's for case when someone wants to be able to move PreparedGeometry freely around, encapsulate in inside some struct etc. I think it's valid case, not something that should be difficult or impossible to do. I have posted some examples in the issue. I don't see the other ways to handle it (or perhaps the answer is to not encapsulate PreparedGeometry anywhere, but that sound very limiting.)
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