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An odd "non-determinism" example from StackOverflow It is clever, but doesn't make much sense as to how it gets its results
author IBBoard <dev@ibboard.co.uk>
date Sun, 14 Jul 2019 13:44:13 +0100
parents 4d3769ac447c
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4d3769ac447c Add notes and code on methods in Io
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1 # Methods are objects, defined by some new notation:
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2 # method(object message[…])
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3
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4 # This would show something in REPL but is useless in normal execution
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5 method("This does nothing but print something, but with the line-break" println)
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6 # Methods are of type "Block"
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7 method() type println
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8 # And they can be assigned to slots like values
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9 Car := Object clone
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10 ferrari := Car clone
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11 Car drive := method("Vroom" println)
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12 # Note that "cloning" isn't a one-time thing - we modified Car after creating
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13 # ferrari, but it now has the `drive` method anyway. This is good, but
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14 # doesn't *quite* match the naming
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15 ferrari drive
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16
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17 # You can also retrieve slots (methods or values), which walks up the heirarchy if necessary
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18 ferrari getSlot("drive") println
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19 # And you can find out what its prototype is
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20 # (i.e. what it inherited from and what exists)
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21 ferrari proto println
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22 # But what if we add something to the ferrari? that isn't covered yet
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23 ferrari name := "My Fast Car"
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24 ferrari proto println
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25 ferrari name println
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26 # It seems to only cover the parent stuff
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27
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28 # There's also a "master namespace" that all the objects get created in:
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29 Lobby println