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posts: generic-flyweight: fix lint issues

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Bruno BELANYI 2020-08-27 17:32:51 +02:00
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content/posts/generic-flyweight-cpp.md
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@ -86,10 +86,12 @@ cannot keep the `vector` sorted to do binary searches and insertion, because
the flyweights rely on their index inside the vector being stable. the flyweights rely on their index inside the vector being stable.
Instead, I'd recommend you use an `std::set` for the following reasons: Instead, I'd recommend you use an `std::set` for the following reasons:
- its semantic implies an ordering relationship, without duplication - its semantic implies an ordering relationship, without duplication
- it has an (asymptotically) efficient insertion. - it has an (asymptotically) efficient insertion.
- it has stable iterators/pointers on insertion: a flyweight can just refer to - it has stable iterators/pointers on insertion: a flyweight can just refer to
a pointer to the object contained inside the `std::set`. a pointer to the object contained inside the `std::set`.
That last bullet point is the reason why I'd recommend using a `set` instead of That last bullet point is the reason why I'd recommend using a `set` instead of
a sorted `vector`. a sorted `vector`.
@ -110,13 +112,13 @@ public:
``` ```
The little `&(*instances_.emplace(c))` does all the work for us: The little `&(*instances_.emplace(c))` does all the work for us:
- `instances_.emplace(c)` creates the corresponding metadata only if it isn't in - `instances_.emplace(c)` creates the corresponding metadata only if it isn't in
the set already. the set already.
- We get an iterator back to the inserted element from this operation - We get an iterator back to the inserted element from this operation
- We dereference it (`*<IT>`) to get a `GlyphMetadata&` - We dereference it (`*<IT>`) to get a `GlyphMetadata&`
- We take the address of that reference for our flyweight (`&(<REF>)`). - We take the address of that reference for our flyweight (`&(<REF>)`).
### Templating ### Templating
This scheme with an `std::set` is easily templatable: indeed we can imagine a This scheme with an `std::set` is easily templatable: indeed we can imagine a