Strange negation operator behaviour?

The following line in a motion program reports no errors in the IDE but will not download:

Motor[1].HomeVel = -Motor[1].HomeVel;

Is there something wrong with this syntactically?

The error message is (unhelpfully) "Error : ( error #31) invalid parameter number in equation".

The following similar lines work (the last one being how I get around the error):

Motor[1].HomeVel = -100;
Motor[1].HomeVel = -GlobalVar;
Motor[1].HomeVel = -(Motor[1].HomeVel);

daves,

I have duplicated the problem and reported to firmware developers, awaiting corrective action.

Regards,

daves,

The firmware development team says that structures don't have a negation bit, hence we can't use structures in following format:

NOT ACCEPTABLE: P0=-Motor[1].ServoCtrl

but we can do the following, as you have already found out:

ACCEPTABLE: p0=-(Motor[1].ServoCtrl)

ACCEPTABLE: P0=0-Motor[1].ServoCtrl