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Merged
merged 1 commit into from
Nov 25, 2019
Merged

Expand compile_error! #2362

merged 1 commit into from
Nov 25, 2019

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kjeremy
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@kjeremy kjeremy commented Nov 22, 2019

Does not validate that the input is a string literal. I thought that I could match_ast! against the macro_args but that did not work. Even if it had I am not sure which error would be appropriate.


let macro_content = {
// FIXME: verify that this is an ast::Literatal with kind() == LiteralKind.String, else error.
let arg = macro_call.token_tree().ok_or_else(|| mbe::ExpandError::UnexpectedToken)?;
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@edwin0cheng edwin0cheng Nov 22, 2019

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You could get it by using tt , if it is valid , it should be a single subtree with one literal token-tree.

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Okay. Once I have the literal is there an existing funtion to validate it's type or do I need to manually parse the ends and look for quotes?

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@edwin0cheng edwin0cheng Nov 22, 2019

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As I know there is no existing function to validate it, so you may need to check whether it contains double quote. And if I remember correctly, the quote! macro support TokenTree too.

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Even if it had I am not sure which error would be appropriate.

I think we could add a builtin error in mbe::ExpandError::Builtin(String) for now.

@kjeremy kjeremy marked this pull request as ready for review November 22, 2019 20:16
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bjorn3 commented Nov 22, 2019

Could you actually give an error when compile_error is expanded?

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kjeremy commented Nov 22, 2019 via email

match &tt.token_trees[0] {
tt::TokenTree::Leaf(tt::Leaf::Literal(it)) => {
let s = it.text.as_str();
if s.starts_with(r#"""#) && s.ends_with(r#"""#) {
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@edwin0cheng edwin0cheng Nov 23, 2019

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It may be a raw string, which start with r# , just checking whether it contains a double quote will be enough.

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matklad commented Nov 24, 2019

Could you actually give an error when compile_error is expanded?

Nope, there's no infra for macro diagnostics yet

@kjeremy kjeremy force-pushed the expand-compile-error branch from 1f1963c to 67d3600 Compare November 25, 2019 00:02
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bors r+ , Thanks

bors bot added a commit that referenced this pull request Nov 25, 2019
2362: Expand compile_error! r=edwin0cheng a=kjeremy

Does not validate that the input is a string literal. I thought that I could `match_ast!` against the `macro_args` but that did not work. Even if it had I am not sure which error would be appropriate.

Co-authored-by: Jeremy Kolb <[email protected]>
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bors bot commented Nov 25, 2019

Build succeeded

  • Rust
  • TypeScript

@bors bors bot merged commit 67d3600 into rust-lang:master Nov 25, 2019
@kjeremy kjeremy deleted the expand-compile-error branch November 25, 2019 14:48
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4 participants