The mpmath is a library, but I bet some people use it as a mp-calculator. Could we provide more useful interface for interactive work? I think so.

I'll suggest diofant-like interface: https://diofant.readthedocs.io/en/latest/cli.html (which is more or less an equivalent of the isympy script, but uses more robust methods of transformation for code). Given this, per default we could have in python -m mpmath shell something like that:

• from mpmath import * namespace
• integer division (most hateful Python feature) will be transformed to a Fraction (see ensure "gotchas" are easy to find and link to #677) or to accurate mpmath's value (mpf(numerator)/denominator)
• float and complex literals will be transformed to mpf/mpc without truncation (i.e. 10.9 will be mpf('10.9'))

Does this make sense?