In this document, we will use some meta-syntactic features to describe commands. Literal tokens (such as LITERAL-TOKEN) appear in a typewriter font. Non-terminals look like this: non-terminal. The line-feed, carriage-return, and space characters are represented as LF, CR, and SPC, respectively. Alternation (choice among two or more possibilities) looks like: (option1 or option2 )
We also use the following meta-syntactic constructs: