README

This directory contains a single source file, mlr.bnf, which is the lexical/semantic grammar file for the Miller put/filter DSL (domain-specific language) using the PGPG framework. (In a classical Lex/Yacc framework, there would be separate mlr.l and mlr.y files; using PGPG, there is a single mlr.bnf file.)

All subdirectories of pkg/parsing/ are autogen code created by PGPG's processing of mlr.bnf. They are nonetheless committed to source control, since running PGPG takes a bit longer than the go build does, and the BNF file doesn't often change. (BNF is for Backus-Naur Form which is the phrasing of the grammar file that PGPG support.)

Run tools/build-dsl from the repo root to regenerate the lexer and parser.