Plus42 algebraic expressions update

[Vincent Weber]

I think I found a bug in Plus42.
Playing with strings and lists, i don't know how I got there, but I ended up with an "UnsupportedVarType" strange object on the stack. Trying to use "COMPLEX" on 2 identical numbers on X and Y (the strange object being in T) resulted in a surprising "insufficient memory". Deleting the strange object made things back to normal, and the COMPLEX number generation to work fine again.

Any idea ?

Cheers