From 8f997228baca69d4209d6f79756de65051b339d4 Mon Sep 17 00:00:00 2001
From: Caleb Jones <code@calebjones.net>
Date: Wed, 28 Dec 2016 14:10:55 -0500
Subject: [PATCH] Make it possible to take ownership of the strings in a Sexp

This lets you extend the lifetime, which is useful for things like
producing error types that contain an Sexp and so on.
---
 Cargo.toml |  2 +-
 src/lib.rs | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index e14fdac..7e92b66 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "sexp2"
-version = "0.3.0"
+version = "0.3.1"
 authors = ["Caleb Jones <code@calebjones.net>"]
 
 [dependencies]
diff --git a/src/lib.rs b/src/lib.rs
index 25d9060..5067788 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -44,6 +44,27 @@ impl<'a, Loc> Sexp<'a, Loc> where Loc: Span {
     }
 }
 
+fn extend_cow<'a, T: ?Sized>(cow: &Cow<'a, T>) -> Cow<'static, T>
+    where T: ToOwned
+{
+    Cow::Owned(cow.clone().into_owned())
+}
+
+impl<'a, Loc> Sexp<'a, Loc> where Loc: Span + Clone {
+    pub fn to_owned(&self) -> Sexp<'static, Loc> {
+        match *self {
+            Sexp::Sym(ref s, ref l) => Sexp::Sym(extend_cow(s), l.clone()),
+            Sexp::Str(ref s, ref l) => Sexp::Str(extend_cow(s), l.clone()),
+            Sexp::Char(c, ref l) => Sexp::Char(c, l.clone()),
+            Sexp::Int(i, ref l) => Sexp::Int(i, l.clone()),
+            Sexp::Float(f, ref l) => Sexp::Float(f, l.clone()),
+            Sexp::List(ref xs, ref l) =>
+                Sexp::List(xs.iter().map(Sexp::to_owned).collect(),
+                           l.clone()),
+        }
+    }
+}
+
 
 // General Parsing Types ///////////////////////////////////////////////////////
 
-- 
2.43.2