Macro genco::quote_in

quote_in!() { /* proc-macro */ }

Same as [quote!], except that it allows for quoting directly to a token stream.

You specify the destination stream as the first argument, followed by a => and then the code to generate.

Note that there is a potential issue with reborrowing

Reborrowing

In case you get a borrow issue like the following:

9  |   let tokens = &mut tokens;
   |       ------ help: consider changing this to be mutable: `mut tokens`
...
12 | /     quote_in! { tokens =>
13 | |         fn #name() -> u32 {
14 | |             #(tokens => tokens.append("42");)
15 | |         }
16 | |     }
   | |_____^ cannot borrow as mutable

This is because inner scoped like #(tokens => <code>) take ownership of their variable by default. To have it perform a proper reborrow, you can do the following instead:

use genco::prelude::*;

let mut tokens = Tokens::<Rust>::new();
let tokens = &mut tokens;

for name in vec!["foo", "bar", "baz"] {
    quote_in! { tokens =>
        fn #name() -> u32 {
            #(*tokens => tokens.append("42");)
        }
    }
}

Examples

use genco::prelude::*;

let mut tokens = rust::Tokens::new();

quote_in! { tokens =>
    fn foo() -> u32 {
        42
    }
}

Examples

use genco::prelude::*;

let mut tokens = rust::Tokens::new();

quote_in!(tokens => fn hello() -> u32 { 42 });

assert_eq!(vec!["fn hello() -> u32 { 42 }"], tokens.to_file_vec().unwrap());