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END TEXTHASHKEY; |
END TEXTHASHKEY; |
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</syntaxhighlight> |
</syntaxhighlight> |
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=={{header|Skew}}== |
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{{works with|skewc|0.9.19}} |
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In Skew, interfaces must be explicitly implemented with `::`. |
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<syntaxhighlight lang="skew"> |
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@entry |
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def main { |
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var rgb = Rgb.new(0, 255, 255) |
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var hex = Hex.new("00ffff") |
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var color Color |
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color = hex |
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color.print |
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color = rgb |
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color.print |
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(hex as Color).print |
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} |
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interface Color { |
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def toString string |
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def print { |
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dynamic.console.log(self.toString) |
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} |
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} |
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class Rgb :: Color { |
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var r int, g int, b int |
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def toString string { return "rgb(\(r), \(g), \(b))" } |
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} |
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class Hex :: Color { |
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var code string |
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def toString string { return "#\(code)" } |
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} |
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</syntaxhighlight> |
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=={{header|Smalltalk}}== |
=={{header|Smalltalk}}== |
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A class is declared abtract by responding to the query <tt>isAbstract</tt> with true, and defining the required protocol for subclasses to raise an error notification. Optionally, instance creation can be blocked (but seldom done, as you will hit a subclassResponsibility anyway soon). Typically, the IDE provides menu functions to generate these definitions automatically (eg. "Insert Abstract Class" in the refactoring submenu of the class browser): |
A class is declared abtract by responding to the query <tt>isAbstract</tt> with true, and defining the required protocol for subclasses to raise an error notification. Optionally, instance creation can be blocked (but seldom done, as you will hit a subclassResponsibility anyway soon). Typically, the IDE provides menu functions to generate these definitions automatically (eg. "Insert Abstract Class" in the refactoring submenu of the class browser): |
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