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use blocks;
use fileformat::Blob;
use objects::OsmObj;
use osmformat::PrimitiveBlock;
use std::iter;
use Result;
rental! {
mod rent {
use osmformat::PrimitiveBlock;
use blocks;
#[rental]
pub struct OsmObjs {
block: Box<PrimitiveBlock>,
objs: blocks::OsmObjs<'block>,
}
}
}
impl<'a> Iterator for rent::OsmObjs {
type Item = OsmObj;
fn next(&mut self) -> Option<Self::Item> {
self.rent_mut(|objs| objs.next())
}
}
pub struct OsmObjs(OsmObjsImpl);
enum OsmObjsImpl {
OkIter(iter::Map<rent::OsmObjs, fn(OsmObj) -> Result<OsmObj>>),
ErrIter(iter::Once<Result<OsmObj>>),
}
impl Iterator for OsmObjs {
type Item = Result<OsmObj>;
fn next(&mut self) -> Option<Self::Item> {
match self.0 {
OsmObjsImpl::OkIter(ref mut iter) => iter.next(),
OsmObjsImpl::ErrIter(ref mut iter) => iter.next(),
}
}
}
pub fn result_blob_into_iter(result: Result<Blob>) -> OsmObjs {
match result.and_then(|b| ::reader::primitive_block_from_blob(&b)) {
Ok(block) => OsmObjs(OsmObjsImpl::OkIter(new_rent_osm_objs(block).map(Ok))),
Err(e) => OsmObjs(OsmObjsImpl::ErrIter(iter::once(Err(e)))),
}
}
fn new_rent_osm_objs(block: PrimitiveBlock) -> rent::OsmObjs {
rent::OsmObjs::new(Box::new(block), blocks::iter)
}