What should be the best response from a calculator or computer algebra system when it can't evaluate given expression ? Some examples:
LibreCalc : =😁÷🤣 → Err:501 Ubuntu Calculator : 😁÷🤣 → Malformed expression Wolfram Alpha : 😁÷🤣 → Wolfram|Alpha doesn't understand your query Maxima : maxima --very-quiet -r '😁÷🤣;' → 😁÷🤣
Now my personal impressions about these responses:
Some cryptic error code which doesn't say anything about issue at hand. You must then read manuals to understand what's going on. And from version-to-version this error code can change.
This tries to argue that my given expression is somewhat BAD. But you can't be sure about it. It may be bad OR simply calculator engine don't have an internal knowledge how to compute that expression. So this response is too categorical.
Wolfram|Alpha doesn't understand your query
This is much, much better. Shows that computation engine can't parse requested expression. Of course if I would get such answer from a human, I would ask "What you don't understand exactly ?" So still not 100% right.
I choose this as a winner. This program tries to be mathematically correct in each and every way. Every man on the world knows that expression is equal to itself :
x=x. So if you can't evaluate given expression - at least output to the user original expression. It respects my feeling
"Do something !". And it does (at least what it can)
What do you think ?