12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970 |
- [#get_line]
- [section get_line]
- [h1 Synopsis]
- template <class SourcePosition>
- struct get_line;
- This is a [link lazy_metafunction lazy template metafunction].
- [table Arguments
- [[Name] [Type]]
- [[`SourcePosition`] [[link source_position source position]]]
- ]
- [h1 Description]
- Returns the line of a source position.
- [h1 Header]
- #include <boost/metaparse/get_line.hpp>
- [h1 Expression semantics]
- For any `l`, `c` compile-time wrapped integral values and `ch` compile-time
- wrapped character the following are equivalent
- get_line<source_position<l, c, ch>>::type
-
- l::type
- [h1 Example]
- #include <boost/metaparse/get_line.hpp>
- #include <boost/metaparse/source_position.hpp>
-
- #include <type_traits>
-
- using namespace boost::metaparse;
-
- struct returns_source_position
- {
- using type =
- source_position<
- std::integral_constant<int, 11>,
- std::integral_constant<int, 13>,
- std::integral_constant<char, 0>
- >;
- };
-
- static_assert(
- get_line<
- source_position<
- std::integral_constant<int, 11>,
- std::integral_constant<int, 13>,
- std::integral_constant<char, 0>
- >
- >::type::value == 11,
- "It should return the line of a source position"
- );
-
- static_assert(
- get_line<returns_source_position>::type::value == 11,
- "It should support lazy evaluation"
- );
-
- [endsect]
|