Parse decimals in a locale-independent way

[AndyZe]

Motivated by these MoveIt and ros2_control issues:

https://github.com/ros-planning/moveit2/issues/1882

https://github.com/ros-controls/ros2_control/pull/921/files

[AndyZe]

I think galactic-testing is failing because this usage of std::to_chars requires C++17

https://stackoverflow.com/a/63964295

[simonschmeisser]

You need a pretty recent gcc version for floating point support in std::to_char

[AndyZe]

Alright, thanks. What do you recommend to do here @simonschmeisser ?

[simonschmeisser]

First I'd verify the gcc version as the source of the problem, what does galactic mean in terms of Ubuntu? Then probably copy paste the helper function from MoveIt core helpers

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Codecov Report

Base: 67.83% // Head: 67.09% // Decreases project coverage by -0.74% :warning:

Coverage data is based on head (4bb945b) compared to base (91d7db8). Patch coverage: 0.00% of modified lines in pull request are covered.

Additional details and impacted files

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[simonschmeisser]

So it seems a very ugly hack (by actually switching the locale, which is global in c, temporarily) to support floating points in std::from_char was added for gcc 11.1.0, Ubuntu 20.04 defaults to 9.4.0. Proper support seems to have been implemented by now but is not actually released yet ( https://github.com/gcc-mirror/gcc/commits/master/libstdc%2B%2B-v3/src/c%2B%2B17/floating_from_chars.cc ).