Create a function that takes a single (numeric) argument and returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulator (including the initial value passed when the accumulator was created).
Rules:
Do not use global variables.
Hint:
Closures save outer state.
accumulator
is a function.
testString: assert(typeof accumulator === 'function', 'accumulator
is a function.');
- text: accumulator(0)
should return a function.
testString: assert(typeof accumulator(0) === 'function', 'accumulator(0)
should return a function.');
- text: accumulator(0)(2)
should return a number.
testString: assert(typeof accumulator(0)(2) === 'number', 'accumulator(0)(2)
should return a number.');
- text: Passing in the values 3, -4, 1.5, and 5 should return 5.5.
testString: assert(testFn(5) === 5.5, 'Passing in the values 3, -4, 1.5, and 5 should return 5.5.');
```