unibase bnf

it didn't come out too well as text. here it is done better:

<table def>     ::=
<table name>
{<table help>}
<attribute def>
...
 >
<key def>
...
 >
{<association def>}
...
 >
{<classification def>}
...
 >

<table name>     ::=     <simple name>|<alias name>
<simple name>     ::=     <local filename>
<alias name>     ::=     <text>,<simple name>|<simple name>,<file name>
<attribute def>     ::=   
<name>,<width>>{*<dimension>}{<domain>{<domain info>}}
<help>

<key def>     ::=     {<attribute>{,<key def>}}
<association def>     ::=     {<assoc type>}<table>{<key def>}
<assoc type>     ::=     +|-|=|*
<classification def>     ::=     <expression>