Dear GAP Forum,

Rifhat Aleev wrote

do you know that GAP3r4p4 becomes SUPER very strange behavior if you use
the capital F? For example,
gap> F:=E(7);
after that repeated some times similar asignments we have system errors
about function.
Real Example of log file:
gap> E:=E(7)^3+E(7)^4;
E(7)^3+E(7)^4
gap> F:=E(7)^2+E(7)^5;
Error, Function: <function> must be a function
After that GAP does NOT work!!!
What is that?

The problem is that in the line

gap> E:=E(7)^3+E(7)^4;

the function `E' is overwritten,
and when `E(7)' is called in the next input line,
GAP cannot evaluate this because `E' is no longer a function.
(So the problem is not the use of the capital F but of the capital E.)

In the forthcoming version GAP 4,
global variables of GAP such as `E' are write protected,
so the above problem cannot occur in GAP 4.

Kind regards,
Thomas

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