22 lines
797 B
Markdown
22 lines
797 B
Markdown
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# C# Language Design Notes for Sep 6, 2016
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## Agenda
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1. How do we select `Deconstruct` methods?
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# How do we select Deconstruct methods?
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`(int x, var y) = p` cannot just turn into `p.Deconstruct(out int x, out var y)`, because we want it to find a `Deconstruct` method with a more specific type than `int`, e.g. `byte`.
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We should look only at the arity of the `Deconstruct` method. If there's more than one with the given arity, we fail. If necessary, we will then translate this into passing temporary variables to the `Deconstruct` method, instead of the ones declared in the deconstruction. E.g., if `p` has
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``` C#
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void Deconstruct(out byte x, out byte y) ...;
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```
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We would translate it equivalently to:
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``` c#
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p.Deconstruct(out byte __x, out byte __y);
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(int x, int y) = (__x, __y);
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```
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