railroad_dsl-0.1.1 doesn't have any documentation.
A small DSL to generate syntax diagrams using this library.
{...}
is a horizontal stack of connected elements[...]
is a vertical sequence of connected elements<...>
is a choice of multiple options, exactly one of which has to be picked"foobar"
is a terminal'foobar'
is a non-terminal`foobar`
is a comment...?
is an optional element...*...
is a repeated element!
is the empty element
Quotes (and backslashes) can be escaped using backslashes.
For example:
{["CONSTRAINT", "name"]?,
<["PRIMARY", "KEY", <!, "ASC", "DESC">, 'conflict-clause', <!, "AUTOINCREMENT">],
["NOT", "NULL", 'conflict-clause'],
["UNIQUE", 'conflict-clause'],
["CHECK", "(", 'expr', ")"],
["DEFAULT", <'signed-number', 'literal-value', ["(", 'expr', ")"]>],
["COLLATE", "collation-name"],
'foreign-key-clause'>}