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Date:   Mon, 14 Nov 2022 14:26:11 +0000
From:   Gary Guo <gary@garyguo.net>
To:     Miguel Ojeda <ojeda@kernel.org>
Cc:     Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        =?UTF-8?B?QmrDtnJu?= Roy Baron <bjorn3_gh@protonmail.com>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev
Subject: Re: [PATCH v1 05/28] rust: macros: add `concat_idents!` proc macro
Message-ID: <20221114142611.2a21d4e9@GaryWorkstation>
In-Reply-To: <20221110164152.26136-6-ojeda@kernel.org>
References: <20221110164152.26136-1-ojeda@kernel.org>
        <20221110164152.26136-6-ojeda@kernel.org>
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On Thu, 10 Nov 2022 17:41:17 +0100
Miguel Ojeda <ojeda@kernel.org> wrote:

> +pub(crate) fn concat_idents(ts: TokenStream) -> TokenStream {
> +    let mut it = ts.into_iter();
> +    let a = expect_ident(&mut it);
> +    assert_eq!(expect_punct(&mut it), ',');
> +    let b = expect_ident(&mut it);
> +    assert!(it.next().is_none(), "only two idents can be concatenated");
> +    let res = Ident::new(&(a.to_string() + &b.to_string()), b.span());

Probably clearer to write `Ident::new(&format!("{a}{b}"), b.span())`
here?

Best,
Gary