Merge branch 'get_or' to load default value: #6

.travis.yml

@@ -39,4 +39,4 @@ script:
 - git clone https://github.com/toml-lang/toml.git
 - cmake -DCMAKE_CXX_COMPILER=$COMPILER ..
 - make
-- make test
+- ctest --output-on-failure

README.md

@@ -109,6 +109,19 @@ const auto& num1 = numbers.at(1).cast<toml::value_t::Integer>();
 const auto& num2 = numbers.at(2).cast<toml::value_t::Integer>();
 ```
 
+#### toml::get\_or
+
+You can also set default value for `toml::get`.
+
+```cpp
+toml::Table data; // empty table!
+
+const auto value1 = toml::get_or(data, "key1", 42); // value1 => int 42.
+
+toml::Integer i(123);
+const auto value2 = toml::get_or(data, "key1", i);  // value2 => toml::Integer 42.
+```
+
 #### toml::value\_t
 
 When you don't know the exact type of toml-value, you can get `enum` type from

tests/CMakeLists.txt

@@ -5,6 +5,7 @@ set(TEST_NAMES
     test_to_toml
     test_from_toml
     test_get
+    test_get_or
     test_value_operator
     test_datetime
     test_acceptor

tests/test_get_or.cpp

@@ -0,0 +1,88 @@
+#define BOOST_TEST_MODULE "test_get_or"
+#ifdef UNITTEST_FRAMEWORK_LIBRARY_EXIST
+#include <boost/test/unit_test.hpp>
+#else
+#define BOOST_TEST_NO_LIB
+#include <boost/test/included/unit_test.hpp>
+#endif
+#include <toml.hpp>
+#include <map>
+#include <unordered_map>
+#include <list>
+#include <deque>
+#include <array>
+
+
+BOOST_AUTO_TEST_CASE(test_get_or_exist)
+{
+    toml::Boolean  raw_v1(true);
+    toml::Integer  raw_v2(42);
+    toml::Float    raw_v3(3.14);
+    toml::String   raw_v4("hoge");
+    toml::Array    raw_v5{2,7,1,8,2};
+    toml::Table    raw_v6{{"key", 42}};
+
+    toml::value v1(raw_v1);
+    toml::value v2(raw_v2);
+    toml::value v3(raw_v3);
+    toml::value v4(raw_v4);
+    toml::value v5(raw_v5);
+    toml::value v6(raw_v6);
+
+    toml::Table table{
+        {"value1", v1},
+        {"value2", v2},
+        {"value3", v3},
+        {"value4", v4},
+        {"value5", v5},
+        {"value6", v6}
+    };
+
+    toml::Boolean u1 = toml::get_or(table, "value1", raw_v1);
+    toml::Integer u2 = toml::get_or(table, "value2", raw_v2);
+    toml::Float   u3 = toml::get_or(table, "value3", raw_v3);
+    toml::String  u4 = toml::get_or(table, "value4", raw_v4);
+    toml::Array   u5 = toml::get_or(table, "value5", raw_v5);
+    toml::Table   u6 = toml::get_or(table, "value6", raw_v6);
+
+    BOOST_CHECK_EQUAL(u1, raw_v1);
+    BOOST_CHECK_EQUAL(u2, raw_v2);
+    BOOST_CHECK_EQUAL(u3, raw_v3);
+    BOOST_CHECK_EQUAL(u4, raw_v4);
+    BOOST_CHECK_EQUAL(u5.at(0).cast<toml::value_t::Integer>(), raw_v5.at(0).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(1).cast<toml::value_t::Integer>(), raw_v5.at(1).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(2).cast<toml::value_t::Integer>(), raw_v5.at(2).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(3).cast<toml::value_t::Integer>(), raw_v5.at(3).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(4).cast<toml::value_t::Integer>(), raw_v5.at(4).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u6.at("key").cast<toml::value_t::Integer>(), 42);
+}
+
+BOOST_AUTO_TEST_CASE(test_get_or_empty)
+{
+    toml::Boolean  raw_v1(true);
+    toml::Integer  raw_v2(42);
+    toml::Float    raw_v3(3.14);
+    toml::String   raw_v4("hoge");
+    toml::Array    raw_v5{2,7,1,8,2};
+    toml::Table    raw_v6{{"key", 42}};
+
+    toml::Table    table; // empty!
+
+    toml::Boolean  u1 = toml::get_or(table, std::string("value1"), raw_v1);
+    toml::Integer  u2 = toml::get_or(table, std::string("value2"), raw_v2);
+    toml::Float    u3 = toml::get_or(table, std::string("value3"), raw_v3);
+    toml::String   u4 = toml::get_or(table, std::string("value4"), raw_v4);
+    toml::Array    u5 = toml::get_or(table, std::string("value5"), raw_v5);
+    toml::Table    u6 = toml::get_or(table, std::string("value6"), raw_v6);
+
+    BOOST_CHECK_EQUAL(u1, raw_v1);
+    BOOST_CHECK_EQUAL(u2, raw_v2);
+    BOOST_CHECK_EQUAL(u3, raw_v3);
+    BOOST_CHECK_EQUAL(u4, raw_v4);
+    BOOST_CHECK_EQUAL(u5.at(0).cast<toml::value_t::Integer>(), raw_v5.at(0).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(1).cast<toml::value_t::Integer>(), raw_v5.at(1).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(2).cast<toml::value_t::Integer>(), raw_v5.at(2).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(3).cast<toml::value_t::Integer>(), raw_v5.at(3).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u5.at(4).cast<toml::value_t::Integer>(), raw_v5.at(4).cast<toml::value_t::Integer>());
+    BOOST_CHECK_EQUAL(u6.at("key").cast<toml::value_t::Integer>(), 42);
+}

toml/get.hpp

@@ -14,7 +14,7 @@ inline T get(const toml::value& v)
     return static_cast<T>(v.cast<vT>());
 }
 
-// array case
+// array-like type
 template<typename T, toml::value_t vT = toml::detail::check_type<T>(),
          typename std::enable_if<(vT == toml::value_t::Unknown) &&
          (!toml::detail::is_map<T>::value) &&
@@ -24,6 +24,7 @@ T get(const toml::value& v)
     if(v.type() != value_t::Array)
         throw type_error("get: value type: " + stringize(v.type()) +
                          std::string(" is not argument type: Array"));
+
     const auto& ar = v.cast<value_t::Array>();
     T tmp;
     try
@@ -39,6 +40,7 @@ T get(const toml::value& v)
     return tmp;
 }
 
+// table-like case
 template<typename T, toml::value_t vT = toml::detail::check_type<T>(),
          typename std::enable_if<(vT == toml::value_t::Unknown) &&
          toml::detail::is_map<T>::value, std::nullptr_t>::type = nullptr>
@@ -53,5 +55,16 @@ T get(const toml::value& v)
     return tmp;
 }
 
+//  get_or -----------------------------------------------------------------
+
+template<typename T>
+inline typename std::remove_cv<typename std::remove_reference<T>::type>::type
+get_or(const toml::Table& tab, const toml::key& ky, T&& opt)
+{
+    if(tab.count(ky) == 0) {return std::forward<T>(opt);}
+    return get<typename std::remove_cv<
+        typename std::remove_reference<T>::type>::type>(tab.find(ky)->second);
+}
+
 } // toml
 #endif// TOML11_GET