Set parameter bounds for improper integral

[carey]

I tried integrating e^(-s*t) dt between 0 and infinity where s>0, so I set up the integral and used the "where" operator | to set s>0. The correct answer is 1/s but I get syntax errors on my Prime and in the emulator.

The prime emulator screenshots show (i) Home screen attempt; (ii) CAS screen attempt (input); (iii) CAS screen attempt (output).

Thanks for any suggestions!
           

UPDATE:

The correct answer of 1/s can be obtained by typing on the CAS screen:

integrate(e^-s*t,t,0,+infinity)|s>0

After a warning message the Prime displays a pretty printed integral with the correct result.

Screenshots of the CAS input and output in the emulator are attached.

       

Is there a way to obtain the correct result using the integration template?