[1] SliceOpt ::= Slice | ProjectOpt [2] ProjectOpt ::= Project | GroupGraphPatternNoSub [3] GroupGraphPatternNoSub ::= BGP | Join [4] GroupGraphPatternSub ::= BGP | Join | SubSelect [5] SubSelect ::= Slice | Project [6] Slice ::= "(" "slice" ProjectOpt ")" [7] Project ::= "(" "project" "(" (TERM)+ ")" GroupGraphPatternNoSub ")" [8] BGP ::= "(" "bgp" (Triple)+ ")" [9] Triple ::= "(" "triple" TERM TERM TERM ")" [10] Join ::= "(" "join" GroupGraphPatternSub GroupGraphPatternSub ")" [11] ::= "?" ([a-z])+ | "_" ([a-z])+ | "<" ([^>])* ">" | '"' ([^\"])* '"' | "'" ([^'])* "'" [12] PASSED TOKENS ::= ([ \t\r\n])+