# Leap

Given a year, report if it is a leap year.

The tricky thing here is that a leap year in the Gregorian calendar occurs:

```text
on every year that is evenly divisible by 4
  except every year that is evenly divisible by 100
    unless the year is also evenly divisible by 400
```

For example, 1997 is not a leap year, but 1996 is.  1900 is not a leap
year, but 2000 is.

If your language provides a method in the standard library that does
this look-up, pretend it doesn't exist and implement it yourself.

## Notes

Though our exercise adopts some very simple rules, there is more to
learn!

For a delightful, four minute explanation of the whole leap year
phenomenon, go watch [this youtube video][video].

[video]: http://www.youtube.com/watch?v=xX96xng7sAE

## Running Ceylon Tests

Before tests can be run, your code must be compiled via [`ceylon compile`](https://ceylon-lang.org/documentation/current/reference/tool/ceylon/subcommands/ceylon-compile.html).

We run tests with the [`ceylon test`](https://ceylon-lang.org/documentation/reference/tool/ceylon/subcommands/ceylon-test.html) command.

`ceylon test` expects a module name to run the tests on.
In the Ceylon track, each exercise has just a single module.

Therefore, you can run the tests with:

```bash
ceylon compile && ceylon test $(basename source/*)
```

## Source

JavaRanch Cattle Drive, exercise 3 [http://www.javaranch.com/leap.jsp](http://www.javaranch.com/leap.jsp)

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