[llvm] [TableGen] Allow emitter callbacks to use `const RecordKeeper &` (PR #104716)

[Rahul Joshi via llvm-commits]

" + sys::path::filename(Record.getInputFilename()),"
In-Reply-To: <llvm.org/llvm/llvm-project/pull/104716 at github.com>


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@@ -69,6 +69,10 @@ class function_ref<Ret(Params...)> {
   }
 
   explicit operator bool() const { return callback; }
+
+  bool operator==(const function_ref<Ret(Params...)> &Other) const {
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jurahul wrote:

This is needed now because of its use in `cl::OptionValueCopy<FnT>`, which uses the `==` operator. 

https://github.com/llvm/llvm-project/pull/104716