const FRAMEWORK_FORMAL_PREFIXES: &[&str];Expand description
Prefixes of the R names the framework generates (locals such as
.mx_call and .mx_self, the wrappers preamble’s .miniextendr_*
helpers, the .rdata_* helpers #[derive(ExternalPtr)] writes for a
sidecar, the write-time .__MX_* placeholders): a declared formal starting
with one is refused.