2017-12-06 02:06:17 +01:00
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# C# Language Design Notes for Oct 9, 2017
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***Warning: These are raw notes, and still need to be cleaned up. Read at your own peril!***
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# 882 Negated if or negative patterns
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Three approaches
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1. bang outside if condition (then should I do that on while etc, too) `if !(o is int i)`
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2. negative patterns (but not very useful recursively) `not int i`
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3. `is not` as an expression operator
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# 867
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Avoid some statement cliffs...
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Put it in X.X with a note to consider again when we have match expressions
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# 414
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There's a "there" there.
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2018-01-25 22:11:49 +01:00
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We think this should be addressed, and will keep the championing issue to represent it.
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2017-12-06 02:06:17 +01:00
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However, it should be different:
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1. It should not be strongly tied to the `Dictionary<K, V>` type, but be target typed
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2. We should look at initializing immutable objects (also for object and collection initializers)
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3. We already have index initializers. Are they good enough?
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# 973 Declaration expressions
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Last time, we had two issues:
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1. Weren't ready to commit to scoping rules
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2. Weren't sure that we could get decent error recovery on syntax
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1 is dealt with.
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2 was more that it was hard to show intellisense because more things were legal
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Scenario is introduce a local variable in expressions without having to use trivial pattern matching. Also ref.
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We feel like we need to spend more time with it to judge its value. 8.0 for now to trigger that discussion.
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# 881 and 33
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Fits with nullable in 8.0
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# 185
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Settle this in the 7.3 timeframe
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# 187 Blittable
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# 435
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# 287
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# 32
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# 125
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Missing, but not much ask for it
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# 111
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We would want to deal with single parameters. A problem is that discards do not shadow today, whereas identifiers do. We may want to change that.
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# 191
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Need more motivation
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# 190
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Some open design discussions
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#
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