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58 lines
879 B
CoffeeScript
58 lines
879 B
CoffeeScript
puts(if my_special_variable? then false else true)
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my_special_variable: false
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puts(if my_special_variable? then true else false)
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# Existential assignment.
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a: 5
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a: null
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a ?= 10
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b ?= 10
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puts a is 10 and b is 10
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# The existential operator.
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z: null
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x: z ? "EX"
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puts z is null and x is "EX"
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# Only evaluate once.
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counter: 0
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get_next_node: ->
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throw "up" if counter
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counter++
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puts(if get_next_node()? then true else false)
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# Existence chains, soaking up undefined properties:
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obj: {
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prop: "hello"
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}
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puts obj?.prop is "hello"
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print obj.prop?.length is 5
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print obj?.prop?.non?.existent?.property is undefined
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# Soaks and caches method calls as well.
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arr: ["--", "----"]
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puts arr.pop()?.length is 4
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puts arr.pop()?.length is 2
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puts arr.pop()?.length is undefined
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puts arr[0]?.length is undefined
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puts arr.pop()?.length?.non?.existent()?.property is undefined
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