How do you know if you have mastered a programming language

Question

programming
https://www.sololearn.com/discuss/534476/?ref=app

Answer 1

the day u think u are master in a language, that is the day you have most yet to learn..

Answer 2

practically not possible... u can be good or better in it.. but u cannot master in it. within no year every language gets upgraded.. and new features get added.. and learning just the concepts won't master you.. u need to learn their machine level working.. how do the piece of code interact to the machine..
what hexcode gets generated for an statement.. and much more to go in deep

Answer 3

so you can never really master a language