Can I decompose a domain ?

Hello,


resFloat   : Expression Float := cos (4.0 * x) 
resInteger : Expression Float := cos (4 * x) 
resComplex : Expression Complex Integer := exp (3+4*%i)

How can I get Float from resFloat ? Integer from resInteger, etc. 
in a *.input file ?

I want to make functions in *.input file before 
test a change in a *.spad file.

Or, if it's imposible what is the shortest way for creating a *.spad file ?

Have a good day.

Francois