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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 46a807289724
children
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46a807289724 Add a noddy "builder" to show overriding "forward" for missing methods
IBBoard <dev@ibboard.co.uk>
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1 # Altering "forward" in Io is apparently similar to overriding
46a807289724 Add a noddy "builder" to show overriding "forward" for missing methods
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2 # method_missing in Ruby. Except with more to go wrong because
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3 # we have prototypes and not classes.
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4
46a807289724 Add a noddy "builder" to show overriding "forward" for missing methods
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5 # Building arbitrary (basic) XML using a Builder prototype that
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6 # assumes all missing methods are XML tags
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46a807289724 Add a noddy "builder" to show overriding "forward" for missing methods
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8 Builder := Object clone
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46a807289724 Add a noddy "builder" to show overriding "forward" for missing methods
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10 # This is the dangerous method
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11 Builder forward := method(
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12 writeln("<", call message name, ">")
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13 call message arguments foreach(
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14 arg,
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15 # This will trigger another call to forward
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16 # It's not clear why "writeln" would return a string rather than write to the console
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17 # But apparently it does. Because poorly documented Io.
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18 content := self doMessage(arg)
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19 # No strong type checking here - it's all based on string names
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20 if (content type == "Sequence", writeln(content))
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21 )
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22 writeln("</", call message name, ">")
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23 )
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25 Builder ul(
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26 li("Obscure"),
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27 li("Undocumented"),
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28 li("Unclear")
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29 )