A funny null fact I found out after so many years of working with groovy.

Problem

I happen to create a construction like this:

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     if(object?.value > 0) {
        println "did something"        
     } else {
         println "did nothing"
     }

Are you sure what will be printed when object is null?
I must say I wasn’t.

We got used to negate null in groovy like this:

    assert !null == true   

but what about using null with relation operator?

Turns out

All this below will execute:

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    assert null < 0   
    assert null < Integer.MIN_VALUE
    assert null < Double.NEGATIVE_INFINITY

so lets remember.. null is the lower then anything.