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annotate 2-Io/day1-singletons.io @ 93:39084e2b8744

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Add a function for word-aware text wrapping Potentially hugely inefficient because we iterate through the string character by character, but then splitting it first and iterating over words still needs to iterate over the string to know where to split.
author IBBoard <dev@ibboard.co.uk>
date Tue, 18 Jun 2019 21:05:00 +0100
parents 3d41d9d72cc9
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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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)
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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)
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14 nil clone println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
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15 (true == true clone) println
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
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16
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
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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)
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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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27 obj1 := Object clone
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28 obj2 := Object clone
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29 (obj1 == obj2) println
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30
3d41d9d72cc9 Add Day 1 code for Singletons (including booleans)
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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)
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36 obj3 println