if (somevar == undefined) {

what's the syntax for "undefined" or NaN?

trying to say

p == undefined ? p = 0 : p+=x;

'if p isn't yet defined, assign a value of 0, otherwise add x's value to the whatever it is at the moment.'

what's the syntax for "undefined" or NaN?

trying to say

p == undefined ? p = 0 : p+=x;

'if p isn't yet defined, assign a value of 0, otherwise add x's value to the whatever it is at the moment.'

Try...

p=(typeof(p)!='undefined')?p+x:0;

Does this help?

hmm i can't get it to work, probably my error rather than anything wrong with your solution, thanks for the reply.

Can you not usep = (p == null) ? 0 : p + x;