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vendor/scopeguard/README.rst

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+
+scopeguard
+==========
+
+Rust crate for a convenient RAII scope guard that will run a given closure when
+it goes out of scope, even if the code between panics (assuming unwinding panic).
+
+The `defer!` macro and `guard` are `no_std` compatible (require only core),
+but the on unwinding / not on uwinding strategies requires linking to `std`.
+
+Requires Rust 1.20.
+
+
+Please read the `API documentation here`__
+
+__ https://docs.rs/scopeguard/
+
+|build_status|_ |crates|_
+
+.. |build_status| image:: https://travis-ci.org/bluss/scopeguard.svg
+.. _build_status: https://travis-ci.org/bluss/scopeguard
+
+.. |crates| image:: http://meritbadge.herokuapp.com/scopeguard
+.. _crates: https://crates.io/crates/scopeguard
+
+How to use
+----------
+
+.. code:: rust
+
+    #[macro_use(defer)] extern crate scopeguard;
+
+    use scopeguard::guard;
+
+    fn f() {
+        defer!(println!("Called at return or panic"));
+        panic!();
+    }
+
+    use std::fs::File;
+    use std::io::Write;
+
+    fn g() {
+        let f = File::create("newfile.txt").unwrap();
+        let mut file = guard(f, |f| {
+            // write file at return or panic
+            let _ = f.sync_all();
+        });
+        // Access the file through the scope guard itself
+        file.write_all(b"test me\n").unwrap();
+    }
+
+Recent Changes
+--------------
+
+- 1.1.0
+
+  - Change macros (``defer!``, ``defer_on_success!`` and ``defer_on_unwind!``)
+    to accept statements. (by @konsumlamm)
+
+- 1.0.0
+
+  - Change the closure type from ``FnMut(&mut T)`` to ``FnOnce(T)``:
+    Passing the inner value by value instead of a mutable reference is a
+    breaking change, but allows the guard closure to consume it. (by @tormol)
+
+  - Add ``defer_on_success!{}``, ``guard_on_success()`` and ``OnSuccess``
+    strategy, which triggers when scope is exited *without* panic. It's the
+    opposite to ``OnUnwind`` / ``guard_on_unwind()`` / ``defer_on_unwind!{}``.
+
+  - Add ``ScopeGuard::into_inner()``, which "defuses" the guard and returns the
+    guarded value. (by @tormol)
+
+  - Implement ``Sync`` for guards with non-``Sync`` closures.
+
+  - Require Rust 1.20
+
+- 0.3.3
+
+  - Use ``#[inline]`` on a few more functions by @stjepang (#14)
+  - Add examples to crate documentation
+
+- 0.3.2
+
+  - Add crate categories
+
+- 0.3.1
+
+  - Add ``defer_on_unwind!``, ``Strategy`` trait
+  - Rename ``Guard`` → ``ScopeGuard``
+  - Add ``ScopeGuard::with_strategy``.
+  - ``ScopeGuard`` now implements ``Debug``.
+  - Require Rust 1.11
+
+- 0.2.0
+
+  - Require Rust 1.6
+  - Use `no_std` unconditionally
+  - No other changes
+
+- 0.1.2
+
+  - Add macro ``defer!()``