Updated code to work on stable Rust.

Issue mcarton#25

src/attr.rs

@@ -1,5 +1,6 @@
 use std::str::FromStr;
 
+use proc_macro2;
 use quote::ToTokens;
 use syn;
 

src/clone.rs

@@ -1,3 +1,5 @@
+use proc_macro2;
+
 use ast;
 use attr;
 use matcher;

src/cmp.rs

@@ -1,5 +1,7 @@
 // https://github.com/rust-lang/rust/issues/13101
 
+use proc_macro2;
+
 use ast;
 use matcher;
 use syn;

src/debug.rs

@@ -1,3 +1,5 @@
+use proc_macro2;
+
 use ast;
 use attr;
 use matcher;

src/default.rs

@@ -1,3 +1,5 @@
+use proc_macro2;
+
 use ast;
 use attr;
 use syn;

src/hash.rs

@@ -1,3 +1,5 @@
+use proc_macro2;
+
 use ast;
 use attr;
 use matcher;

src/matcher.rs

@@ -6,13 +6,14 @@
 //     * not generic, we use our own `ast`, `synstructure` only knows about `syn`
 //     * missing information (what arm are we in?, what attributes? etc.)
 
+use proc_macro2;
+use quote::ToTokens;
+use syn;
+
 use ast;
 use attr;
 use quote;
 
-use quote::ToTokens;
-use syn;
-
 /// The type of binding to use when generating a pattern.
 #[derive(Debug, Copy, Clone)]
 pub enum BindingStyle {

src/utils.rs

@@ -1,3 +1,5 @@
+use proc_macro2;
+
 use ast;
 use attr;
 use bound;