Boolean chain

Leap
Leap in PowerShell 
function Test-Leap([int] $year) {
    $year % 4 -eq 0 -and $year % 100 -ne 0 -or $year % 400 -eq 0
}

One of the most common approach to solve this exercise based on the given information. First we test if the year is divisible by 4 using modulus, if it return false here then the chain is short circuit and return false. If the year is indeed divisible by 4, then we test whether it can't divisible by 100 or can divisible by 400. If one of those condition return true then our chain will return true, but if both return false then our chain here will return false.

You can visualize the chain like this:

divisible by 4 not divisible by 100 divisible by 400
false (short circuit) => false
true either this is true or this to be true => true
true false false => false

Arithmetic operators

6th Nov 2024 · Found it useful?

Other Approaches to Leap in PowerShell

Other ways our community solved this exercise
function Test-Leap([int] $year) {
    (Get-Time -Year $year -Month 2 -Day 29).Month -eq 2
}
datetime object

Use datetime object and its property. 

function Test-Leap([int] $year) {
    [DateTime]::IsLeapYear($year)
}
built-in method

Use IsLeapYear method of the DateTime class.