In earlier versions of i3, interpreting these commands was done using lex and
yacc, but experience has shown that lex and yacc are not well suited for our
-command language. Therefore, starting from version 4.2, we use a custom parser.
+command language. Therefore, starting from version 4.2, we use a custom parser
+for user commands (not yet for the configuration file).
The input specification for this parser can be found in the file
+parser-specs/commands.spec+. Should you happen to use Vim as an editor, use
:source parser-specs/highlighting.vim to get syntax highlighting for this file