racket/collects/scribblings/scribble/bnf.scrbl
2010-05-02 12:00:44 -06:00

60 lines
1.8 KiB
Racket

#lang scribble/doc
@(require scribble/manual
"utils.ss"
(for-label scribble/bnf))
@title[#:tag "bnf"]{BNF Grammars}
@defmodule[scribble/bnf]{The @racket[scribble/bnf] library
provides utilities for typesetting grammars.}
See also @racket[racketgrammar].
@defproc[(BNF [prod (cons element? (listof element?))] ...) table?]{
Typesets a grammar table. Each production starts with an element
(typically constructed with @racket[nonterm]) for the non-terminal
being defined, and then a list of possibilities (typically constructed
with @racket[BNF-seq], etc.) to show on separate lines.}
@defproc[(nonterm (pre-content any/c) ...) element?]{
Typesets a non-terminal: italic in angle brackets.}
@defproc[(BNF-seq [elem element?] ...) element?]{
Typesets a sequence.}
@defproc[(BNF-group [pre-content any/c] ...) element?]{
Typesets a group surrounded by curly braces (so the entire group can
be repeated, for example).}
@defproc[(optional [pre-content any/c] ...) element?]{
Typesets an optional element: in square brackets.}
@defproc[(kleenestar [pre-content any/c] ...) element?]{
Typesets a 0-or-more repetition.}
@defproc[(kleeneplus [pre-content any/c] ...) element?]{
Typesets a 1-or-more repetition.}
@defproc[(kleenerange [n any/c] [m any/c] [pre-content any/c] ...) element?]{
Typesets a @racket[n]-to-@racket[m] repetition. The @racket[n] and
@racket[m] arguments are converted to a string using @racket[(format
"~a" n)] and @racket[(format "~a" m)].}
@defproc[(BNF-alt [elem element?] ...) element?]{
Typesets alternatives for a production's right-hand side to appear on
a single line. The result is normally used as a single possibility in
a production list for @racket[BNF].}
@defthing[BNF-etc string?]{
A string to use for omitted productions or content.}