Lexgen fails to work with NSID's that feature Rust keywords

[videah]

I've been trying to generate some type definitions for leaflet.pub's lexicons but the use of pub in their NSID causes lexgen to bail with the error:

cargo run -p lexgen -- --lexdir $HOME/Git/zine/lexicons
   Compiling lexgen v0.1.0 (/Users/videah/Git/zine/crates/lexicon/lexgen)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
     Running `target/debug/main --lexdir /Users/videah/Git/zine/lexicons`

Error: Error("expected identifier, found keyword `pub`")