Determine if a word or phrase is an isogram.

An isogram (also known as a "nonpattern word") is a word or phrase without a repeating letter, however spaces and hyphens are allowed to appear multiple times.

Examples of isograms:

• lumberjacks
• background
• downstream
• six-year-old

The word isograms, however, is not an isogram, because the s repeats.

Go through the setup instructions for JavaScript to install the necessary dependencies:

http://exercism.io/languages/javascript/installation

The provided test suite uses Jasmine. You can install it by opening a terminal window and running the following command:

npm install -g jasmine

Run the test suite from the exercise directory with:

jasmine isogram.spec.js

In many test suites all but the first test have been marked "pending". Once you get a test passing, activate the next one by changing xit to it.

Wikipedia https://en.wikipedia.org/wiki/Isogram

It's possible to submit an incomplete solution so you can see how others have completed the exercise.