4 stable releases
3.0.4 | Aug 26, 2023 |
---|---|
2.0.3 | Nov 9, 2020 |
1.0.3 | Nov 9, 2020 |
1.0.2 | Nov 8, 2020 |
1.0.0 |
|
#143 in Procedural macros
144 downloads per month
Used in 5 crates
(3 directly)
14KB
69 lines
call2-for-syn
This library provides a call2
function that sits somewhere in-between syn
's parse2
and ParseBuffer::call
: It lets you conveniently apply a parser function to a proc-macro2
token stream, for example from a quote!
.
Installation
Please use cargo-edit to always add the latest version of this library:
cargo add call2-for-syn
Example
use call2_for_syn::{call2_allow_incomplete, call2_strict};
use quote::quote;
use syn::{ext::IdentExt as _, Ident, Token};
use unquote::unquote;
let (now, is) = call2_strict(
quote!(Now is...),
|input| {
let now: Ident = input.parse()?;
let is: Ident = input.parse()?;
// input.parse::<Token![!]>()?;
syn::Result::Ok((now, is))
},
).unwrap_err().parsed.unwrap(); // Use ? here in a real program.
assert_eq!(format!("{}", now), "Now");
assert_eq!(format!("{}", is), "is");
let (a, good, time) = call2_strict(
quote!(...a good time...),
|input| {
let a: Ident;
let good: Ident;
let time: Ident;
unquote!(input, ... #a #good #time ...);
syn::Result::Ok((a, good, time))
},
).unwrap().unwrap(); // Use ? here in a real program.
assert_eq!(format!("{}", a), "a");
assert_eq!(format!("{}", good), "good");
assert_eq!(format!("{}", time), "time");
let (r#for, parsing) = call2_allow_incomplete(
quote!(for parsing!),
|input| {
let r#for = input.call(Ident::parse_any)?;
let parsing: Ident = input.parse()?;
// input.parse::<Token![!]>()?;
syn::Result::Ok((r#for, parsing))
},
).unwrap(); // Use ? here in a real program.
assert_eq!(format!("{}", r#for), "for");
assert_eq!(format!("{}", parsing), "parsing");
License
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.
See CONTRIBUTING for more information.
Code of Conduct
Changelog
Versioning
call2-for-syn
strictly follows Semantic Versioning 2.0.0 with the following exceptions:
- The minor version will not reset to 0 on major version changes (except for v1).
Consider it the global feature level. - The patch version will not reset to 0 on major or minor version changes (except for v0.1 and v1).
Consider it the global patch level.
This includes the Rust version requirement specified above.
Earlier Rust versions may be compatible, but this can change with minor or patch releases.
Which versions are affected by features and patches can be determined from the respective headings in CHANGELOG.md.
Note that dependencies of this crate may have a more lenient MSRV policy!
Please use cargo +nightly update -Z minimal-versions
in your automation if you don't generate Cargo.lock manually (or as necessary) and require support for a compiler older than current stable.
Dependencies
~250–690KB
~17K SLoC