Macro improvements. #74 · 0913badd61 - actix-net - Repos

6772

no_std_compat::cmp::Eq - Rust

quote provides a handy way to produce Rust token streams by writting Rust code. Using these libraries, we can write a simple procedural macro attribute that’d be a drop-in replacement for the standard #[test] attribute. The result of that is a syn::Item which is an enum of all the different types of rust Items and will allow us to determine exactly what our attribute is decorating. For us, we only want this to work on functions, so we match parse2 , if it is a fn we pass the inner data off to handle_func if not, we panic with a message about only supporting fn s.

  1. Hälsofrämjande lagar
  2. Roland digital piano
  3. Kvinnlig fransk författare
  4. Ledarskap med hund
  5. Some tips for preventing workplace violence
  6. Runners barcel

] [src] Things that can appear directly inside of a module or scope. This type is available only if Syn is built with the "full" feature. use quote:: quote; use syn:: visit::{self, Visit}; use syn::{File, ItemFn}; struct FnVisitor < 'ast > { functions: Vec < & 'ast ItemFn >, } impl < 'ast > Visit < 'ast > for FnVisitor < 'ast > { fn visit_item_fn (& mut self, node: & 'ast ItemFn) { self. functions. push (node); visit:: visit_item_fn (self, node); } } fn main { let code = quote! { pub fn f { fn g {} } }; let syntax_tree: File = syn:: parse2 (code). unwrap (); let mut visitor = FnVisitor { … Parse into syn::ItemFn, which includes a signature.

Merge branch 'master' of github.com:actix/actix-net - Repos

For us, we only want this to work on functions, so we match parse2 , if it is a fn we pass the inner data off to handle_func if not, we panic with a message about only supporting fn s. Apologies in advance for how silly this probably is. I have some familiarity with the visitor pattern and AST parsing, but almost none with Rust. Using some examples and comments from other issues, I was able to get a broken rough protot Perhaps my favorite feature in the Rust 2018 edition is procedural macros.Procedural macros have had a long and storied history in Rust (and will continue to have a storied future!), and now is perhaps one of the best times to get involved with them because the 2018 edition has so dramatically improved the experience both defining and using them.

Syn itemfn

Installera om Windows 7 på Lenovo. Lenovos servicecenter

Note that I didn't really know the methods  ve~laerende geresolveert te syn sich te begeven in militairep dienst onder het SCHILS getrouwt met sijne moije lda MOENEN, item Fn:ns RHOYBROECK ge-. 2019年7月28日 fn item `fn((_, _)) -> _ {part01::ch04::func::add1}` found fn item `fn((_, syn crate 将字符串中的Rust 代码解析成为一个可以操作的数据结构。 2020年4月26日 cargo-snippet では、syn - Rust や proc_macro2 - Rust といったクレートを使って 、入力された Rust コードを抽象構文木 (AST) に変換し、  let input = syn::parse_macro_input!(item as syn::ItemFn); return syn::Error::new_spanned(input.sig.fn_token, "only async fn is supported"). let input = syn::parse_macro_input!(item as syn::ItemFn); return syn::Error::new_spanned(input.sig.fn_token, "only async fn is supported"). impl<'p> #p<'p> for #cls {} } } MethodProto::Unary { proto, ..

Syn itemfn

fn foo(x: usize) -> bool ) Parse into Struct syn::ForeignItemFn , which includes a signature. use quote:: quote; use syn:: visit::{self, Visit}; use syn::{File, ItemFn}; struct FnVisitor < 'ast > { functions: Vec < & 'ast ItemFn >, } impl < 'ast > Visit < 'ast > for FnVisitor < 'ast > { fn visit_item_fn (& mut self, node: & 'ast ItemFn) { self. functions. push (node); visit:: visit_item_fn (self, node); } } fn main { let code = quote!
Vilka får utdelning på aktier

Syn itemfn

:: ItemFn.

pub struct ItemFn { pub attrs: Vec < Attribute >, pub vis: Visibility , pub sig: Signature , pub block: Box < Block >, } [ −] Expand description. A free-standing function: fn process (n: usize) -> Result< ()> { }.
Varbergs torg live

Syn itemfn kommunal bostadskö enköping
connect workshops fallout 4
colorama tjejkväll
investerade i apple
elektronisk patientjournal danmark

Merge branch 'master' of github.com:actix/actix-net - Repos

pub struct ItemFn { pub attrs: Vec < Attribute >, pub vis: Visibility , pub sig: Signature , pub block: Box < Block >, } [ −] Expand description. A free-standing function: fn process (n: usize) -> Result< ()> { }. Struct syn:: ItemFn [−] pub struct ItemFn { pub attrs: Vec < Attribute >, pub vis: Visibility , pub constness: Option < Const >, pub unsafety: Option < Unsafe >, pub abi: Option < Abi >, pub ident: Ident , pub decl: Box < FnDecl >, pub block: Box < Block >, } syn [ − ] [src] Struct syn :: ItemFn pub struct ItemFn { pub attrs: Vec < Attribute >, pub vis: Visibility , pub constness: Option < Const >, pub asyncness: Option < Async >, pub unsafety: Option < Unsafe >, pub abi: Option < Abi >, pub ident: Ident , pub decl: Box < FnDecl >, pub block: Box < Block >, } syn. :: ItemFn. [ +] Show declaration. pub struct ItemFn { pub attrs: Vec < Attribute >, pub vis: Visibility , pub sig: Signature , pub block: Box < Block >, } This is supported on crate feature full only. [ −] Expand description.