syntax_data: {"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:         /// Right now it's always `$sysroot/lib/rustlib/rustc-src/rust`
context_before:         /// Base directory containing the `compiler/` directory for the rustc sources.
context_after:         /// (i.e. the `rustup` `rustc-dev` component).