v7.3 Q's re patterns:

[RexJaeschke]

In Draft PR #61, I've added all the edits to support the addition of patterns.

During my research, I came across the following text on some web site that claims to be pattern-related:

In C# 7.3 we added the following contexts [https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-7.3/expression-variables-in-initializers] in which a pattern variable may be declared:

• If the expression is in a constructor initializer, its scope is the constructor initializer and the constructor's body.
• If the expression is in a field initializer, its scope is the equals_value_clause in which it appears.
• If the expression is in a query clause that is specified to be translated into the body of a lambda, its scope is just that expression.

As I didn't understand how this might impact my patterns spec, I'm creating this issue for someone else to look at this list.

[RexJaeschke]

I have completed spec'ing the V7.3 feature to add 3 extra places in which out variables and pattern-generated local variables are permitted. The edits for these were applied to PRs 44 and 61. As such, this issue can be closed without further action.