Assignment without defining variable first

Currently all variables have to be defined by a data statement, before they can be used. This leads to clumsy code.
Currently all variables have to be defined by a data statement, before they can be used.
This leads to clumsy code.

Therefore implement assignment without defining the variable first (no data statement.)

 * Maybe limit feature to body of functions.
- Maybe limit feature to body of functions.

 * However if type inference and role inference finally works there should be no problem to allow it everywhere.
- However if type inference and role inference finally works there should be no problem
   * Inferring the role of "a + b", for which an intermediate variable has to be possibly created is the same as inferring the role of "c" in "c = a + b".
  to allow it everywhere.
  - Inferring the role of "a + b", for which an intermediate variable has to be possibly created
    is the same as inferring the role of "c" in "c = a + b".

 * Putting function arguments into the function's namespace could be handled this way too. A unified mechanism would simplify the interpreter.
- Putting function arguments into the function's namespace could be handled this way too.
  A unified mechanism would simplify the interpreter.

https://sourceforge.net/apps/trac/freeode/ticket/8