[PATCH] D74681: [mlir][DeclarativeParser] Add basic support for optional groups in the assembly format.

[River Riddle via Phabricator via llvm-commits]

rriddle added inline comments.


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Comment at: mlir/docs/OpDefinitions.md:655
+  // of operands.
+  let assemblyFormat = "attr-dict ($operands? `:` type($operands))";
+}
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antiagainst wrote:
> antiagainst wrote:
> > It's sort of counter intuitive for me to see this. I'd assume something like `($operands` `:` type($operands))?` would be more natural. But maybe that's drawing too much from regex background. What about something like `($operands^` `:` type($operands))?` so one uses `^` to mean anchor and still retain overall similarity with regex?
> Reformat:
> 
> 
> It's sort of counter intuitive for me to see this. I'd assume something like `($operands : type($operands))?` would be more natural. But maybe that's drawing too much from regex background. What about something like `($operands^ : type($operands))?` so one uses `^` to mean anchor and still retain overall similarity with regex?
I was reaching for something like this but glossed over using ^. Looks much better now, thanks Lei!


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D74681/new/

https://reviews.llvm.org/D74681