[−][src]Macro genco::prelude::quote
quote!() { /* proc-macro */ }
Quotes the specified expression as a stream of tokens for use with genco.
Mechanisms
- Elements are interpolated using
#
, so to include the variabletest
, you could write#test
. Returned elements must implementFormatTokens
. - Inline statements can be evaluated using
#(<stmt>)
, or#{<stmt>}
, or#[<stmt>]
. In effect, anything that counts as a group in Rust. For example:#("test".quoted())
can be used to quote a string. - The
register
functionality of [Tokens
] is available by prefixing an expression with@
as@<stmt>
. For example:@only_imports
. #
and@
can be escaped by repeating it twice in case it's needed in the target language. So##
would produce a single#
, and@@
would produce a single@
.
Examples
#![feature(proc_macro_hygiene)] use genco::rust::imported; use genco::{quote, Rust, Tokens}; // Import the LittleEndian item, without referencing it through the last // module component it is part of. let little_endian = imported("byteorder", "LittleEndian").qualified(); let big_endian = imported("byteorder", "BigEndian"); // This is a trait, so only import it into the scope (unless we intent to // implement it). let write_bytes_ext = imported("byteorder", "WriteBytesExt").alias("_"); let tokens: Tokens<Rust> = quote! { @write_bytes_ext let mut wtr = vec![]; wtr.write_u16::<#little_endian>(517).unwrap(); wtr.write_u16::<#big_endian>(768).unwrap(); assert_eq!(wtr, vec![5, 2, 3, 0]); }; println!("{}", tokens.to_file_string().unwrap());