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frontmatter

The tracking issue for this feature is: #136889


The frontmatter feature allows an extra metadata block at the top of files for consumption by external tools. For example, it can be used by cargo-script files to specify dependencies.

#!/usr/bin/env -S cargo -Zscript --- [dependencies] libc = "0.2.172" --- #![feature(frontmatter)] mod libc { pub type c_int = i32; } fn main() { let x: libc::c_int = 1i32; }