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annotate 2-Io/day1-singletons.io @ 40:82627dd71c75

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Implement 2D list/array
author IBBoard <dev@ibboard.co.uk>
date Thu, 14 Sep 2017 20:24:25 +0100
parents 3d41d9d72cc9
children
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3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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1 # Conditions are simple and like most languages
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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2 # Not mentioned yet, but found by necessity: we can use brackets!
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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3 (4 < 5) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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4 # Unlike Python, Io uses lower case for booleans
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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5 (true and false) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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6 # Truthy values are more like Python than C:
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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7 (true and 6) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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8 (true and 0) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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9
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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10 # But true, false and nil are all just objects
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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11 # Albeit special "singleton" objects where cloning gets the same object
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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12 true clone println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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13 false clone println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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14 nil clone println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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15 (true == true clone) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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16
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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17 # We can create our own singletons by altering the clone method to return the class
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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18 # Highlander: THERE CAN BE ONLY ONE!
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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19 Highlander := Object clone
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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20 Highlander clone := Highlander
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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21 Highlander println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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22 Highlander clone println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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23 highlander1 := Highlander clone
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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24 highlander2 := Highlander clone
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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25 (highlander1 == highlander2) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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26 # Normally cloning gives different objects with different IDs
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IBBoard <dev@ibboard.co.uk>
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27 obj1 := Object clone
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IBBoard <dev@ibboard.co.uk>
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28 obj2 := Object clone
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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29 (obj1 == obj2) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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30
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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31 # And with great power comes great responsibility.
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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32 # Object is not special. It is not protected in any way.
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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33 # DO NOT do this in real code!
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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34 Object clone := "Ooops!"
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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35 obj3 := Object clone
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
IBBoard <dev@ibboard.co.uk>
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36 obj3 println