The wiggle() function returns a vector of the same size as the property that its being called from, it could 1,2 or 3 values:
[0] X
[1] Y
[2] Z

So this will NOT work:

temp = wiggle(10,50);

Because the function is returning 2 values, while the property (assuming it is position in this example) would accept just one for X ad one for Y.

But this will do:

temp = wiggle(10,50);


temp = wiggle(10,50);

This is how to write the expression for a 3 dimensional property:

[ 100,100, [100+wiggle(0.5,200)[2]] ]