Merge pull request #31 from easyaspi314/master

Conditionally enable the exception-throwing constructors

README.md

@@ -50,6 +50,8 @@ or:
 ```c++
 mmap.map(path, error);
 ```
+**NOTE:** The constructors **require** exceptions to be enabled. If you prefer
+to build your projects with `-fno-exceptions`, you can still use the other ways.
 
 Moreover, in each case, you can provide either some string type for the file's path, or you can use an existing, valid file handle.
 ```c++

include/mio/mmap.hpp

@@ -103,6 +103,7 @@ public:
      */
     basic_mmap() = default;
 
+#ifdef __cpp_exceptions
     /**
      * The same as invoking the `map` function, except any error that may occur
      * while establishing the mapping is wrapped in a `std::system_error` and is
@@ -127,6 +128,7 @@ public:
         map(handle, offset, length, error);
         if(error) { throw std::system_error(error); }
     }
+#endif // __cpp_exceptions
 
     /**
      * `basic_mmap` has single-ownership semantics, so transferring ownership

include/mio/shared_mmap.hpp

@@ -87,6 +87,7 @@ public:
         return *this;
     }
 
+#ifdef __cpp_exceptions
     /**
      * The same as invoking the `map` function, except any error that may occur
      * while establishing the mapping is wrapped in a `std::system_error` and is
@@ -111,6 +112,7 @@ public:
         map(handle, offset, length, error);
         if(error) { throw std::system_error(error); }
     }
+#endif // __cpp_exceptions
 
     /**
      * If this is a read-write mapping and the last reference to the mapping,