From 08a98b4a65f8d577ab7815e4ca6733781f3a49d9 Mon Sep 17 00:00:00 2001
From: Sean Griffin <sean@seantheprogrammer.com>
Date: Fri, 22 Apr 2016 14:58:17 -0600
Subject: [PATCH 1/3] Add a `lifetime` specifier to `macro_rules!`

---
 text/0000-macro-lifetimes.md | 49 ++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 text/0000-macro-lifetimes.md

diff --git a/text/0000-macro-lifetimes.md b/text/0000-macro-lifetimes.md
new file mode 100644
index 00000000000..91facfb8435
--- /dev/null
+++ b/text/0000-macro-lifetimes.md
@@ -0,0 +1,49 @@
+- Feature Name: Allow `lifetime` specifiers to be passed to macros
+- Start Date: 2016-04-22
+- RFC PR: (leave this empty)
+- Rust Issue: (leave this empty)
+
+# Summary
+[summary]: #summary
+
+Add a `lifetime` specifier for `macro_rules!` patterns, that matches any valid
+lifetime.
+
+# Motivation
+[motivation]: #motivation
+
+Certain classes of macros are completely impossible without the ability to pass
+lifetimes. Specifically, anything that wants to implement a trait from inside of
+a macro is going to need to deal with lifetimes eventually. They're also
+commonly needed for any macros that need to deal with types in a more granular
+way than just `ty`.
+
+Since a lifetime is a single token, there is currently no way to accept one
+without an explicit matcher. Something like `'$lifetime:ident` will fail to
+compile.
+
+# Detailed design
+[design]: #detailed-design
+
+This RFC proposes adding `lifetime` as an additional specifier to
+`macro_rules!` (alternatively: `life` or `lt`). Since a lifetime acts very much
+like an identifier, and can appear in almost as many places, it can be handled
+almost identically. A preliminary implementation can be found at
+https://github.com/rust-lang/rust/pull/33135
+
+# Drawbacks
+[drawbacks]: #drawbacks
+
+None
+
+# Alternatives
+[alternatives]: #alternatives
+
+A more general specifier, such as a "type parameter list", which would roughly
+map to `ast::Generics` would cover most of the cases that matching lifetimes
+individually would cover.
+
+# Unresolved questions
+[unresolved]: #unresolved-questions
+
+None

From 942c40ed55af07930ded53a523c5571a74bcdf16 Mon Sep 17 00:00:00 2001
From: Sean Griffin <sean@seantheprogrammer.com>
Date: Sat, 23 Apr 2016 08:49:13 -0600
Subject: [PATCH 2/3] Note that `tt` can be used to match a lifetime

---
 text/0000-macro-lifetimes.md | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/text/0000-macro-lifetimes.md b/text/0000-macro-lifetimes.md
index 91facfb8435..6b29deb19fa 100644
--- a/text/0000-macro-lifetimes.md
+++ b/text/0000-macro-lifetimes.md
@@ -18,9 +18,11 @@ a macro is going to need to deal with lifetimes eventually. They're also
 commonly needed for any macros that need to deal with types in a more granular
 way than just `ty`.
 
-Since a lifetime is a single token, there is currently no way to accept one
-without an explicit matcher. Something like `'$lifetime:ident` will fail to
-compile.
+Since a lifetime is a single token, the only way to match against a lifetime is
+by capturing it as `tt`. Something like `'$lifetime:ident` would fail to
+compile. This is extremely limiting, as it becomes difficult to sanitize input,
+and `tt` is extremely difficult to use in a sequence without using awkward
+separators.
 
 # Detailed design
 [design]: #detailed-design

From 17d68e5f0054d1e809c3f9c1ec64fadf64bc9be8 Mon Sep 17 00:00:00 2001
From: Sean Griffin <sean@seantheprogrammer.com>
Date: Wed, 27 Apr 2016 18:13:24 -0600
Subject: [PATCH 3/3] Add an explicit mention of the follow rules for the
 specifier

---
 text/0000-macro-lifetimes.md | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/text/0000-macro-lifetimes.md b/text/0000-macro-lifetimes.md
index 6b29deb19fa..0580cd0ab31 100644
--- a/text/0000-macro-lifetimes.md
+++ b/text/0000-macro-lifetimes.md
@@ -28,9 +28,12 @@ separators.
 [design]: #detailed-design
 
 This RFC proposes adding `lifetime` as an additional specifier to
-`macro_rules!` (alternatively: `life` or `lt`). Since a lifetime acts very much
+`macro_rules!` (alternatively: `life` or `lt`). As it is a single token, it is
+able to be followed by any other specifier. Since a lifetime acts very much
 like an identifier, and can appear in almost as many places, it can be handled
-almost identically. A preliminary implementation can be found at
+almost identically.
+
+A preliminary implementation can be found at
 https://github.com/rust-lang/rust/pull/33135
 
 # Drawbacks