JESS is your friendly neighbourhood JavaScript pre‐compiler. She allows you to tie in transformation modules that make your language more friendly.
She supports two modes of operation: as a source compiler, and as a wrapping
interpreter. These correspond to the two included binaries: jess and
jessc.
jessc operates when passed some JESS sourcefiles, and possibly, a
destination. The sourcefiles will be read, compiled into JavaScript, and
output to the destination.
jess is instead used directly…
Finally, you can acquire jess.js (yes, she’s plain JavaScript; I don’t want
to get into a chicken/egg situation where I can’t compile JESS herself into
workable source) and use jess.process() directly in your own code. How you
apply this is, obviously, up to you.