From 483eb2f56657e8e7f419ab1a4fab8dce9ade8609 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 20:24:20 +0200 Subject: Adding upstream version 14.2.21. Signed-off-by: Daniel Baumann --- src/boost/libs/contract/example/features/old.cpp | 41 ++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 src/boost/libs/contract/example/features/old.cpp (limited to 'src/boost/libs/contract/example/features/old.cpp') diff --git a/src/boost/libs/contract/example/features/old.cpp b/src/boost/libs/contract/example/features/old.cpp new file mode 100644 index 00000000..bdf8b8c6 --- /dev/null +++ b/src/boost/libs/contract/example/features/old.cpp @@ -0,0 +1,41 @@ + +// Copyright (C) 2008-2018 Lorenzo Caminiti +// Distributed under the Boost Software License, Version 1.0 (see accompanying +// file LICENSE_1_0.txt or a copy at http://www.boost.org/LICENSE_1_0.txt). +// See: http://www.boost.org/doc/libs/release/libs/contract/doc/html/index.html + +#include +#include +#include + +//[old +char replace(std::string& s, unsigned index, char x) { + char result; + boost::contract::old_ptr old_char; // Null, old value copied later... + boost::contract::check c = boost::contract::function() + .precondition([&] { + BOOST_CONTRACT_ASSERT(index < s.size()); + }) + .old([&] { // ...after preconditions (and invariants) checked. + old_char = BOOST_CONTRACT_OLDOF(s[index]); + }) + .postcondition([&] { + BOOST_CONTRACT_ASSERT(s[index] == x); + BOOST_CONTRACT_ASSERT(result == *old_char); + }) + ; + + result = s[index]; + s[index] = x; + return result; +} +//] + +int main() { + std::string s = "abc"; + char r = replace(s, 1, '_'); + assert(s == "a_c"); + assert(r == 'b'); + return 0; +} + -- cgit v1.2.3