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# Classes are reference types
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class Job {
var title = ""
}
var job1 = Job()
var job2 = job1
job1.title = "singer"
print(job2.title) // singer
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Triple equals checks identity.
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print(job1 === job2) // true
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# Dictionaries are copied at the point of assignment
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var band1 = ["bob": "singer", "dan": "guitarist"]
var band2 = band1
band2["bob"] = "drummer"
print(band1["bob"]) // singer
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# Arrays, Strings, and Dictionaries
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Arrays, Strings, and Dictionaries are implemented as structs,
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so they're copied when they're assigned to a new constant or
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variable, or when they'e passed to a function / method
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var bands1 = ["radiohead", "telekinesis", "nada surf"]
var bands2 = bands1
print(bands1 == bands2) // true
bands1[0] = "the orwells"
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Now bands2 is a separate copy.
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print(bands2[0]) // radiohead
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