A little more regex source generator tweaking

[stephentoub]

Couldn't help myself :) It's fun just looking at what code the generator writes for varying regexes and finding ways to improve it a bit here and there.

cc: @joperezr

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Issue Details

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Couldn't help myself :) It's fun just looking at what code the generator writes for varying regexes and finding ways to improve it a bit here and there.

cc: @joperezr

Author:	stephentoub
Assignees:	-
Labels:	area-System.Text.RegularExpressions
Milestone:	-

[GSPP]

It's probably good to get quality high for the first release. After that, any further improvements could cause massive source control diffs when the generators are re-run.

[stephentoub]

After that, any further improvements could cause massive source control diffs when the generators are re-run.

I'm not concerned about that. These source generators are intended to be run as part of every build, by default the source that's generated isn't even saved to disk, and even if you opt-in to saving it to disk, it's saved to a temporary location. Limiting innovation here because of concerns around improvements to the source generator would be akin to saying compilers shouldn't improve from version to version.