And especially the topmost comment by stephencanon (highlights): https://news.ycombinator.com/item?id=16514962 https://news.ycombinator.com/item?id=16514962 "

And especially the topmost comment by stephencanon (highlights): https://news.ycombinator.com/item?id=16514962 https://news.ycombinator.com/item?id=16514962 "If you want a default decimal floating-point type, the only defensible choice is the decimal128 type standardized by IEEE 754. It has a fully-defined arithmetic, specified by experts who have spent their careers thinking about the issues involved, and is wide enough to exactly represent the US national debt in every currency used on earth. There are situations where other decimal floating-point types are appropriate, but if you do not understand the tradeoffs you are making, you should be using decimal128." and "I would be remiss not to note that Intel has made available a well-tested complete implementation of IEEE 754 decimal64 and decimal128 under 3-clause BSD: http://www.netlib.org/misc/intel/ http://www.netlib.org/misc/intel/ "