---

yaml
---
r: 224437
b: refs/heads/beta
c: c3c9d91
h: refs/heads/master
i:
  224435: 37391db
v: v3

Author: Gankra

[refs]

@@ -23,7 +23,7 @@ refs/tags/0.9: 36870b185fc5f5486636d4515f0e22677493f225
 refs/tags/0.10: ac33f2b15782272ae348dbd7b14b8257b2148b5a
 refs/tags/0.11.0: e1247cb1d0d681be034adb4b558b5a0c0d5720f9
 refs/tags/0.12.0: f0c419429ef30723ceaf6b42f9b5a2aeb5d2e2d1
-refs/heads/beta: 74b398b93d647237acbc1c738e55e47ec13ea7b2
+refs/heads/beta: c3c9d9140530a9709449fd32e830bf88f567845c
 refs/tags/1.0.0-alpha: e42bd6d93a1d3433c486200587f8f9e12590a4d7
 refs/heads/tmp: 938f5d7af401e2d8238522fed4a612943b6e77fd
 refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f

branches/beta/lifetimes.md

@@ -447,15 +447,9 @@ The variance of `*const` and `*mut` is basically arbitrary as they're not at all
 type or memory safe, so their variance is determined in analogy to & and &mut
 respectively.
 
-
-
-
-## PhantomData
-
 This is all well and good for the types the standard library provides, but
-how is variance determined for type that *you* define? A struct is, informally
-speaking, covariant over all its fields (and an enum over its variants). This
-basically means that it inherits the variance of its fields. If a struct `Foo`
+how is variance determined for type that *you* define? A struct informally
+speaking inherits the variance of its fields. If a struct `Foo`
 has a generic argument `A` that is used in a field `a`, then Foo's variance
 over `A` is exactly `a`'s variance. However this is complicated if `A` is used
 in multiple fields.
@@ -478,6 +472,17 @@ struct Foo<'a, 'b, A, B, C, D, E, F, G, H> {
 }
 ```
 
+
+
+
+## Dropck
+
+TODO
+
+
+## PhantomData
+
+
 However when working with unsafe code, we can often end up in a situation where
 types or lifetimes are logically associated with a struct, but not actually
 part of a field. This most commonly occurs with lifetimes. For instance, the `Iter`
@@ -511,6 +516,8 @@ pub struct Iter<'a, T: 'a> {
 }
 ```
 
+However PhantomData is also necessary to signal important information to
+*dropck*. (TODO)