Emacs Demo Mode

Hi, I am trying to run a file of Singular commands in the Demo Emacs mode. I am getting errors like:

? error occurred in STDIN line 41: 'poly f2 = +2x0y1+sx1y1+1x0y2+1x1y2;'
? expected poly-expression. type 'help poly;'
? last reserved name was 'poly'
? incompatible type in list assignment

....

Is there any special format I need for the emacs file that I am trying to run? I just have a file titled testSing2.sing, which has the contents:

ring R=0,(x,y,z),dp;
poly f1 = 4x0y0+3x1y0+2x2y0+1x1y1+2x0y2+1x1y2+3x2y2;
poly f2 = +2x0y1+2x1y1+1x0y2+1x1y2;
poly f3 = -1x1y0+2x0y1+1x1y1+1x2y1+1x1y2+2x2y2;
ideal i = f1,f2,f3,1-xyz;
ideal sm2 = liftstd(i,T);
sm2;
print(T);



Does this file need any special headers, syntax, etc, so that it can be run in the Singular demo mode? I am new to Singular, so any help would be appreciated!

Thank you,
Gina Upperman

The special format of the emacs demo mode is simply
an empty line: it separates the inputs
(each time you press return in the demo mode window,
the file contents till the next empty line will be send to Singular).

But this does not help in this case:
Singular simply does not have an unary +:
write
poly f2= 2x....
and it should work.