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3.4.4.1 Formal account

The following grammar describes the syntax of syntactic data in terms of various kinds of lexemes defined in the grammar in Lexical Syntax 

<datum> -> <lexeme datum>
         | <compound datum>
<lexeme datum> -> <boolean> | <number>
         | <character> | <string> | <symbol>
<symbol> -> <identifier>
<compound datum> -> <list> | <vector> | <bytevector>
<list> -> (<datum>*) | [<datum>*]
         | (<datum>+ . <datum>) | [<datum>+ . <datum>]
         | <abbreviation>
<abbreviation> -> <abbrev prefix> <datum>
<abbrev prefix> -> ' | ` | , | ,@
         | #' | #` | #, | #,@
<vector> -> #(<datum>*)
<bytevector> -> #vu8(<u8>*)
<u8> -> <any <number> representing an exact integer in {0, ..., 255}>