To include a custom function as an option for defining a format. This would allow users to write their own number format function, or share these functions with each other, without the need to create a new revision to AutoIncr each time a new format is added.
E.g. increments using fractional does not work at present. So create a defun called AInc:Custom:Fractional which has inputs for the number to be converted, the number of digits & the precision to be used. It would then simply use the built-in AutoLisp function of rtos but with mode 5 (fractional) instead of the current mode 2 (decimal).
To have something even more involved would then also be possible. The rtos mode 1 gives Scientific format, while the mode 3 "Engineering (feet and decimal inches) is not what an engineer would want to display large numbers. Engineering notation is much the same as Scientific, but the exponent increments / decrements in factors of 3. Thus 10000 would be written as 10+E3 instead of Scientific's way of 1+E4. The custom function should be able to handle this.
See the SVN: http://caddons.svn.sourceforge.net/viewvc/caddons/General/AutoIncr.LSP?view=log
Revision 23 adds this functionality