https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/errors/metavar_exprs/index.html
rustc_expand::errors::metavar_exprs - Rust
API documentation for the Rust `metavar_exprs` mod in crate `rustc_expand`.
rustcexpanderrors
https://www-auth.cs.wisc.edu/lists/htcondor-users/2005-April/msg00119.shtml
Re: [Condor-users] HOSTALLOW_CONFIG in STARTD_EXPRS
condorusersconfig
https://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Statement-Exprs.html
Statement Exprs - Using the GNU Compiler Collection (GCC)
Using the GNU Compiler Collection (GCC)
gnu compiler collectionstatementusinggcc