Difference between revisions of "C++17"

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This table lists C++14 and C++17 features and whether they can be used in Inkscape or not (yet).
 
This table lists C++14 and C++17 features and whether they can be used in Inkscape or not (yet).
 
Add C++14 or C++17 features that you would like to use to the table, so that we know what to test for to increase the C++17 "allowance".
 
Add C++14 or C++17 features that you would like to use to the table, so that we know what to test for to increase the C++17 "allowance".
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See also [[C++11]]
  
 
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Latest revision as of 09:10, 17 April 2020

Usage status

This table lists C++14 and C++17 features and whether they can be used in Inkscape or not (yet). Add C++14 or C++17 features that you would like to use to the table, so that we know what to test for to increase the C++17 "allowance".

See also C++11

Feature Since Can use? Comment
std::move and rvalues C++11 from 1.0 Allows passing ownership of internal resources between objects
enum class C++11 from 1.1 Strong enum constants (take the name of the enum, can't be implicitly converted to int)
std::make_unique<Foo>(…) C++14 from 1.1 Replaces std::unique_ptr<Foo>(new Foo(…))
constexpr C++14 from 1.1 Declares a variable as usable in a const expression
if constexpr C++17 from 1.1 Guarantees the branches will be decided at compile-time
std::variant<…> C++17 from 1.1 Type-safe union, where the contained type is known at runtime
std::optional<…> C++17 from 1.1 Object type (not a pointer or reference) which can either exist or be std::nullopt
auto [x, y] = foo(); C++17 from 1.1 Structured binding, for returning more than a single value
namespace A::B::C C++17 from 1.1 Nested namespaces
inline static const int C++17 from 1.1 Inline variables (inside header files)
std::filesystem C++17 not yet Filesystem library (may not be useful as we are using Gio::File). Also only supported from gcc 8, and Ubuntu 18.04 only has gcc 7.
toxic feature of doom NO Never use this (in case we stumble upon C++14/C++17 features that we really don't like)

Platform status

We need to keep coordinated with the section on Distro Dependencies.

Also see this page:

Note that __cplusplus is always 1 for GCC 4.6 that is used on Windows. So #if __cplusplus < 201103L or variants does not work to choose between C++03 or C++11 code.

C++17 is well supported by all major compilers.

Compiler version when feature complete:

GCC Clang MSVC
C++17 7 (2017) 4 (2017) (5 for constexpr lambda expressions) 19.14 (2017)
C++20 10* 10* 19.22#

'*' Mostly complete '#' About half complete