Actually add RFC 532

text/0532-self-in-use.md

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+- Start Date: 2014-12-19
+- RFC PR: [532](https://github.com/rust-lang/rfcs/pull/532)
+- Rust Issue: [20361](https://github.com/rust-lang/rust/issues/20361)
+
+# Summary
+
+This RFC proposes the `mod` keyword used to refer
+the immediate parent namespace in `use` items (`use a::b::{mod, c}`)
+to be changed to `self`.
+
+# Motivation
+
+While this looks fine:
+
+````rust
+use a::b::{mod, c};
+
+pub mod a {
+    pub mod b {
+        pub type c = ();
+    }
+}
+````
+
+This looks strange, since we are not really importing a module:
+
+````rust
+use Foo::{mod, Bar, Baz};
+
+enum Foo { Bar, Baz }
+````
+
+RFC #168 was written when there was no namespaced `enum`,
+therefore the choice of the keyword was suboptimal.
+
+# Detailed design
+
+This RFC simply proposes to use `self` in place of `mod`.
+This should amount to one line change to the parser,
+possibly with a renaming of relevant AST node (`PathListMod`).
+
+# Drawbacks
+
+`self` is already used to denote a relative path in the `use` item.
+While they can be clearly distinguished
+(any use of `self` proposed in this RFC will appear inside braces),
+this can cause some confusion to beginners.
+
+# Alternatives
+
+Don't do this.
+Simply accept that `mod` also acts as a general term for namespaces.
+
+Allow `enum` to be used in place of `mod` when the parent item is `enum`.
+This clearly expresses the intent and it doesn't reuse `self`.
+However, this is not very future-proof for several reasons.
+
+* Any item acting as a namespace would need a corresponding keyword.
+  This is backward compatible but cumbersome.
+* If such namespace is not defined with an item but only implicitly,
+  we may not have a suitable keyword to use.
+* We currently import all items sharing the same name (e.g. `struct P(Q);`),
+  with no way of selectively importing one of them by the item type.
+  An explicit item type in `use` will imply that we *can* selectively import,
+  while we actually can't.
+
+# Unresolved questions
+
+None.