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author | Robin Krahl <robin.krahl@ireas.org> | 2020-01-07 11:18:04 +0000 |
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committer | Daniel Mueller <deso@posteo.net> | 2020-01-08 09:20:25 -0800 |
commit | 5e20a29b4fdc8a2d442d1093681b396dcb4b816b (patch) | |
tree | 55ab083fa8999d2ccbb5e921c1ffe52560dca152 /syn/src/parse_macro_input.rs | |
parent | 203e691f46d591a2cc8acdfd850fa9f5b0fb8a98 (diff) | |
download | nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.gz nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.bz2 |
Add structopt dependency in version 0.3.7
This patch series replaces argparse with structopt in the argument
handling code. As a first step, we need structopt as a dependency.
Import subrepo structopt/:structopt at efbdda4753592e27bc430fb01f7b9650b2f3174d
Import subrepo bitflags/:bitflags at 30668016aca6bd3b02c766e8347e0b4080d4c296
Import subrepo clap/:clap at 784524f7eb193e35f81082cc69454c8c21b948f7
Import subrepo heck/:heck at 093d56fbf001e1506e56dbfa38631d99b1066df1
Import subrepo proc-macro-error/:proc-macro-error at 6c4cfe79a622c5de8ae68557993542be46eacae2
Import subrepo proc-macro2/:proc-macro2 at d5d48eddca4566e5438e8a2cbed4a74e049544de
Import subrepo quote/:quote at 727436c6c137b20f0f34dde5d8fda2679b9747ad
Import subrepo rustversion/:rustversion at 0c5663313516263059ce9059ef81fc7a1cf655ca
Import subrepo syn-mid/:syn-mid at 5d3d85414a9e6674e1857ec22a87b96e04a6851a
Import subrepo syn/:syn at e87c27e87f6f4ef8919d0372bdb056d53ef0d8f3
Import subrepo textwrap/:textwrap at abcd618beae3f74841032aa5b53c1086b0a57ca2
Import subrepo unicode-segmentation/:unicode-segmentation at 637c9874c4fe0c205ff27787faf150a40295c6c3
Import subrepo unicode-width/:unicode-width at 3033826f8bf05e82724140a981d5941e48fce393
Import subrepo unicode-xid/:unicode-xid at 4baae9fffb156ba229665b972a9cd5991787ceb7
Diffstat (limited to 'syn/src/parse_macro_input.rs')
-rw-r--r-- | syn/src/parse_macro_input.rs | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/syn/src/parse_macro_input.rs b/syn/src/parse_macro_input.rs new file mode 100644 index 0000000..d6e0725 --- /dev/null +++ b/syn/src/parse_macro_input.rs @@ -0,0 +1,110 @@ +/// Parse the input TokenStream of a macro, triggering a compile error if the +/// tokens fail to parse. +/// +/// Refer to the [`parse` module] documentation for more details about parsing +/// in Syn. +/// +/// [`parse` module]: crate::rustdoc_workaround::parse_module +/// +/// <br> +/// +/// # Intended usage +/// +/// This macro must be called from a function that returns +/// `proc_macro::TokenStream`. Usually this will be your proc macro entry point, +/// the function that has the #\[proc_macro\] / #\[proc_macro_derive\] / +/// #\[proc_macro_attribute\] attribute. +/// +/// ``` +/// extern crate proc_macro; +/// +/// use proc_macro::TokenStream; +/// use syn::{parse_macro_input, Result}; +/// use syn::parse::{Parse, ParseStream}; +/// +/// struct MyMacroInput { +/// /* ... */ +/// } +/// +/// impl Parse for MyMacroInput { +/// fn parse(input: ParseStream) -> Result<Self> { +/// /* ... */ +/// # Ok(MyMacroInput {}) +/// } +/// } +/// +/// # const IGNORE: &str = stringify! { +/// #[proc_macro] +/// # }; +/// pub fn my_macro(tokens: TokenStream) -> TokenStream { +/// let input = parse_macro_input!(tokens as MyMacroInput); +/// +/// /* ... */ +/// # "".parse().unwrap() +/// } +/// ``` +#[macro_export(local_inner_macros)] +macro_rules! parse_macro_input { + ($tokenstream:ident as $ty:ty) => { + match $crate::parse_macro_input::parse::<$ty>($tokenstream) { + $crate::export::Ok(data) => data, + $crate::export::Err(err) => { + return $crate::export::TokenStream::from(err.to_compile_error()); + } + } + }; + ($tokenstream:ident) => { + parse_macro_input!($tokenstream as _) + }; +} + +//////////////////////////////////////////////////////////////////////////////// +// Can parse any type that implements Parse. + +use crate::parse::{Parse, ParseStream, Parser, Result}; +use proc_macro::TokenStream; + +// Not public API. +#[doc(hidden)] +pub fn parse<T: ParseMacroInput>(token_stream: TokenStream) -> Result<T> { + T::parse.parse(token_stream) +} + +// Not public API. +#[doc(hidden)] +pub trait ParseMacroInput: Sized { + fn parse(input: ParseStream) -> Result<Self>; +} + +impl<T: Parse> ParseMacroInput for T { + fn parse(input: ParseStream) -> Result<Self> { + <T as Parse>::parse(input) + } +} + +//////////////////////////////////////////////////////////////////////////////// +// Any other types that we want `parse_macro_input!` to be able to parse. + +#[cfg(any(feature = "full", feature = "derive"))] +use crate::AttributeArgs; + +#[cfg(any(feature = "full", feature = "derive"))] +impl ParseMacroInput for AttributeArgs { + fn parse(input: ParseStream) -> Result<Self> { + let mut metas = Vec::new(); + + loop { + if input.is_empty() { + break; + } + let value = input.parse()?; + metas.push(value); + if input.is_empty() { + break; + } + input.parse::<Token![,]>()?; + } + + Ok(metas) + } +} |