[PATCH] D83855: [clang] Fix printing of lambdas with capture expressions

[Kadir Cetinkaya via Phabricator via cfe-commits]

kadircet added inline comments.


================
Comment at: clang/lib/AST/StmtPrinter.cpp:2011
+      Expr *Init = D->getInit();
+      if (D->getInitStyle() == VarDecl::CallInit && !isa<ParenListExpr>(Init))
+        OS << "(";
----------------
walrus wrote:
> kadircet wrote:
> > what about having a `Pre` and `Post` print blocks, set to `"(" and ")"` or `" = ` and ""` respectively?
> > 
> > that way we could get rid of the second if block below.
> > 
> > 
> > also i don't follow why blacklisting for parenlistexpr is needed here (i can see that it will end up printing double parens, but so is `ParenExpr`s, and I think both of them shouldn't be showing up as initializer exprs of captured variables), could you elaborate with a comment and a test case?
> I think you're right that skipping `ParenListExpr` is wrong here. I took this part of code from DeclPrinter. The `ParenListExpr`s are skipped when printing variable declarations, but I think it is not applicable when printing lambda expression captures.
> 
> Honestly, I didn't get about `Pre` and `Post` blocks. I know it is supported when printing types, but I could not find how to do this for expressions.
i meant something like below, (modulo naming):
```
llvm::StringRef Pre;
llvm::StringRef Post;
if(Style == CallInit) {
  Pre = "(";
  Post = ")";
}
else if (Style == CInit)
  Pre = " = ";

OS << Pre;
PrintExpr(Init):
OS << Post;
```


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D83855/new/

https://reviews.llvm.org/D83855