[llvm] [CAS] Add llvm-cas tools to inspect on-disk LLVMCAS (PR #166481)

[Petr Hosek via llvm-commits]

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@@ -0,0 +1,63 @@
+include "llvm/Option/OptParser.td"
+
+class F<string name> : Flag<["--", "-"], name>;
+
+def grp_action : OptionGroup<"Actions">, HelpText<"llvm-cas actions">;
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petrhosek wrote:

Have you considered using subcommands for actions? The subcommand support was introduced in https://github.com/llvm/llvm-project/pull/155026.

https://github.com/llvm/llvm-project/pull/166481