I have the following function -

```
def add (*nums)
  nums.reduce(:+)
end

def subtract(first, *rest)
  first - rest.reduce(:+)
end

def calculate(*nums, options)
  first = nums.first
  rest = nums.reverse.drop(1)
  add(*nums) if options.size == 0
end     

```

The following is the error I receive when invoking the function - 

> 
> syntax error, unexpected '=', expecting ')' def calculate(\*nums,
>  options={}) ^
> 
> 
> 

What is the error in my syntax ?