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I've got this line of code:
console.log "source = #{@source.alignment} unit = #{unit.alignment}: " + (@source.alignment is not unit.alignment)
This is printing this out to the console:
source = good unit = bad: false
Why is it printing "false"? Shouldn't it be printing "true"? Logically, good "is not" bad.
This
console.log "source = #{@source.alignment} unit = #{unit.alignment}: " + (@source.alignment != unit.alignment)
prints
source = good unit = bad: true
as expected.
What's the difference? When should I use is not?
935
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It's an operator precedence issue:
a is not b => a is (not b)
That means that this compiles to the next js:
a === !b
In your case, b is unit.alignment, and as that var exists and its value is not falsy, !unit.alignment returns false
To solve your problem, check out isnt operator in Coffeescript docs
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