Are BigFloats unable to exactly represent 0.1?

[Sukera]

It’s for the same reason that 0.1 + 0.2 != 0.3 (https://0.30000000000000004.com)

@roflmaostc

How does the show method know that we want to see 0.1 and not the real value that’s stored?

Julia prints the shortest value that uniquely identifies the float in question when parsed back. The algorithm in question is called “Ryu”, you can find the julia implementation here.