Skip to content

Production-annotated Turtle Grammar #3752

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
afs merged 1 commit into from
Feb 14, 2026
+236 −174
Merged

Production-annotated Turtle Grammar #3752

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
162 changes: 98 additions & 64 deletions jena-arq/Grammar/Turtle/turtle.jj
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,9 @@
* SPDX-License-Identifier: Apache-2.0
*/

// Turtle RDF 1.1 Grammar.
// Turtle RDF 1.2 Grammar.
// https://www.w3.org/TR/rdf12-turtle/#sec-grammar
//
// This is not the usual parser used by RIOT.
// RIOT has it's own tokenizer/parser which is faster.
// This grammar exists as a more convenient base for new languages
Expand Down Expand Up @@ -71,16 +73,22 @@ PARSER_END(TurtleJavacc)
void parse(): { }
{
ByteOrderMark()
(Statement())*
TurtleDoc()
<EOF>
}

// Turtle [1] -- turtleDoc ::= statement*
void TurtleDoc() : {}
{
(Statement())*
}

void ByteOrderMark() : {}
{
(<BOM>)?
}

// Turtle [2] statement
// Turtle [2] -- statement ::= directive | (triples '.')
void Statement() : {}
{
Directive()
Expand All @@ -90,7 +98,7 @@ void Statement() : {}
| (Triples() <DOT> )
}

// Turtle [3] directive
// Turtle [3] -- directive ::= ... | sparqlPrefix | sparqlBase | sparqlVersion
void Directive() : { Token t ; String iri ; String verStr ;}
{
<PREFIX> t = <PNAME_NS> iri = IRIREF()
Expand All @@ -104,6 +112,21 @@ void Directive() : { Token t ; String iri ; String verStr ;}
{ declareVersion(verStr, t.beginLine, t.beginColumn); }
}

// Turtle [3] -- directive ::= prefixID | base | version | ...
void DirectiveOld() : { Token t ; Token t2 ; String iri ; String verStr ; }
{
<PREFIX_OLD> t = <PNAME_NS> iri = IRIREF() <DOT>
{ String s = canonicalPrefix(t.image, t.beginLine, t.beginColumn) ;
setPrefix(s, iri, t.beginLine, t.beginColumn) ; }
|
t = <BASE_OLD> iri = IRIREF() <DOT>
{ setBase(iri, t.beginLine, t.beginColumn) ; }
|
t = <VERSION_OLD> verStr = VersionSpecificer() <DOT>
{ declareVersion(verStr, t.beginLine, t.beginColumn); }
}

// Turtle [10] -- VersionSpecifier ::= STRING_LITERAL_QUOTE | STRING_LITERAL_SINGLE_QUOTE
String VersionSpecificer() : { Token t; String verStr; }
{

Expand All @@ -119,19 +142,9 @@ String VersionSpecificer() : { Token t; String verStr; }
}
}

void DirectiveOld() : { Token t ; Token t2 ; String iri ; String verStr ; }
{
<PREFIX_OLD> t = <PNAME_NS> iri = IRIREF() <DOT>
{ String s = canonicalPrefix(t.image, t.beginLine, t.beginColumn) ;
setPrefix(s, iri, t.beginLine, t.beginColumn) ; }
|
t = <BASE_OLD> iri = IRIREF() <DOT>
{ setBase(iri, t.beginLine, t.beginColumn) ; }
|
t = <VERSION_OLD> verStr = VersionSpecificer() <DOT>
{ declareVersion(verStr, t.beginLine, t.beginColumn); }
}

// Turtle [11] -- triples ::= (subject predicateObjectList)
// | (blankNodePropertyList predicateObjectList?)
// | (reifiedTriple predicateObjectList?)
void Triples() : { Node n; }
{
n = Subject() PredicateObjectList(n)
Expand All @@ -141,32 +154,45 @@ void Triples() : { Node n; }
n = ReifiedTriple() ( PredicateObjectList(n) )?
}

// Turtle [12] -- predicateObjectList ::= verb objectList (';' (verb objectList)?)*
void PredicateObjectList(Node s) : { Node p = null ; }
{
p = Verb()
ObjectList(s, p)
(<SEMICOLON> (p = Verb() ObjectList(s, p))? )*
}

// Turtle [13] -- objectList ::= object annotation (',' object annotation)*
void ObjectList(Node s, Node p): { Node o ; }
{
o = Object()
{ emitTriple(s, p, o, token.beginLine, token.beginColumn) ; }
Annotation(s, p, o)
// Strict
(
<COMMA> o = Object()
{ emitTriple(s, p, o, token.beginLine, token.beginColumn) ; }
Annotation(s, p, o)
)*
}

// Turtle [9] verb
// // Trailing comma allowed
// (
// <COMMA>
// (
// o = Object()
// { emitTriple(s, p, o, token.beginLine, token.beginColumn) ; }
// Annotation(s, p, o)
// )?
// )*
}

// Turtle [14] -- verb ::= predicate | 'a'
Node Verb() : { Node p ; }
{
( p = Predicate() | <KW_A> { p = nRDFtype ; } )
{ return p ; }
}

// Turtle [15] -- subject ::= iri | BlankNode | collection
Node Subject() : { Node s; String iri ; }
{
(
Expand All @@ -179,14 +205,15 @@ Node Subject() : { Node s; String iri ; }
{ return s ; }
}

// Turtle [11] predicate
// Turtle [16] -- predicate ::= verb
Node Predicate() : { String iri;}
{
iri = iri()
{ return createURI(iri, token.beginLine, token.beginColumn); }
}

// Turtle [12] object
// Turtle [17] -- object ::= iri | BlankNode | collection | blankNodePropertyList
// | literal | tripleTerm | reifiedTriple
Node Object(): { Node o ; String iri; }
{
( iri = iri() { o = createURI(iri, token.beginLine, token.beginColumn) ; }
Expand All @@ -200,15 +227,15 @@ Node Object(): { Node o ; String iri; }
{ return o; }
}

// Turtle [13] literal
// Turtle [18] literal ::= RDFLiteral | NumericLiteral | BooleanLiteral
Node Literal() : { Node n ;}
{
n = RDFLiteral() { return n ; }
| n = NumericLiteral() { return n ; }
| n = BooleanLiteral() { return n ; }
}

// Turtle [14] blankNodePropertyList
// Turtle [19] -- blankNodePropertyList ::= '[' predicateObjectList ']'
Node BlankNodePropertyList() : { Token t ; }
{
t = <LBRACKET>
Expand All @@ -218,9 +245,8 @@ Node BlankNodePropertyList() : { Token t ; }
{ return n ; }
}

// Turtle [15] collection
Node Collection() :
{ Node listHead = nRDFnil ; Node lastCell = null ; int mark ; Node n ; Token t ; }
// Turtle [20] -- collection ::= '(' object* ')'
Node Collection() : { Node listHead = nRDFnil ; Node lastCell = null ; int mark ; Node n ; Token t ; }
{
t = <LPAREN>
{ int line = t.beginLine; int column = t.beginColumn;
Expand All @@ -246,14 +272,14 @@ Node Collection() :
return listHead ; }
}

// Turtle: Gramnmar has "object" directly in the collection rule.
// Turtle: Grammar has "object" directly in the collection rule.
Node CollectionElt() : { Node o;}
{
o = Object()
{ return o; }
}

// Turtle [16] NumericLiteral
// Turtle [21] -- NumericLiteral ::= INTEGER | DECIMAL | DOUBLE
Node NumericLiteral() : { Token t ; }
{
(
Expand All @@ -263,7 +289,7 @@ Node NumericLiteral() : { Token t ; }
)
}

// Turtle [128s] RDFLiteral
// Turtle [22] -- RDFLiteral ::= String (LANG_DIR | ('^^' iri))?
Node RDFLiteral() : { Token t ; String lex = null ; }
{
lex = String()
Expand All @@ -277,28 +303,18 @@ Node RDFLiteral() : { Token t ; String lex = null ; }
{ return createLiteral(lex, lang, uri, token.beginLine, token.beginColumn) ; }
}

String LangTag() : { Token t ; }
{
// Enumerate the directives here because they look like language tags.
( t = <LANG_DIR> | t = AnyDirective() )
{ String lang = stripChars(t.image, 1) ; return lang ; }
}

Token AnyDirective() : { Token t ; }
{
( t = <PREFIX_OLD> | t = <BASE_OLD> | t = <VERSION_OLD> )
{ return t ; }
}

// Turtle [133s] BooleanLiteral
// Turtle [23] -- BooleanLiteral ::= 'true' | 'false'
Node BooleanLiteral() : {}
{
<TRUE> { return XSD_TRUE ; }
|
<FALSE> { return XSD_FALSE ; }
}

// Turtle [17] String
// Turtle [24] -- String ::= STRING_LITERAL_QUOTE
// | STRING_LITERAL_SINGLE_QUOTE
// | STRING_LITERAL_LONG_SINGLE_QUOTE
// | STRING_LITERAL_LONG_QUOTE
String String() : { Token t ; String lex ; }
{
( t = <STRING_LITERAL1> { lex = stripQuotes(t.image) ; }
Expand All @@ -312,15 +328,15 @@ String String() : { Token t ; String lex ; }
}
}

// Turtle [135s] iri
// Turtle [25] -- iri ::= IRIREF | PrefixedName
String iri() : { String iri ; }
{
iri = IRIREF() { return iri ; }
|
iri = PrefixedName() { return iri ; }
}

// Turtle [136s] PrefixedName
// Turtle [26] -- PrefixedName ::= PNAME_LN | PNAME_NS
String PrefixedName() : { Token t ; }
{
( t = <PNAME_LN>
Expand All @@ -331,7 +347,7 @@ String PrefixedName() : { Token t ; }
)
}

// Turtle [137s] BlankNode
// Turtle [27] -- BlankNode ::= BLANK_NODE_LABEL | ANON
Node BlankNode() : { Token t = null ; }
{
t = <BLANK_NODE_LABEL>
Expand All @@ -341,12 +357,7 @@ Node BlankNode() : { Token t = null ; }

}

String IRIREF() : { Token t ; }
{
t = <IRIref>
{ return resolveQuotedIRI(t.image, t.beginLine, t.beginColumn) ; }
}

// Turtle [28] -- reifier ::= '~' (iri | BlankNode)?
Node Reifier() : { Node n = null; String iriStr; Token t; }
{
t = <TILDE>
Expand All @@ -358,6 +369,7 @@ Node Reifier() : { Node n = null; String iriStr; Token t; }
{ return n ; }
}

// Turtle [29] -- reifiedTriple ::= '<<' rtSubject verb rtObject reifier? '>>'
Node ReifiedTriple() : { Node reifId = null ; Token tok ; Node s; Node p ; Node o ; }
{
tok = <LT2>
Expand All @@ -370,7 +382,7 @@ Node ReifiedTriple() : { Node reifId = null ; Token tok ; Node s; Node p ; Node
{ return reifId ; }
}

// rtSubject
// Turtle [30] -- rtSubject ::= iri | BlankNode | reifiedTriple
Node ReifiedTripleSubject() : { Node s; String iri; } {
( iri = iri() { s = createURI(iri, token.beginLine, token.beginColumn) ; }
| s = BlankNode()
Expand All @@ -379,7 +391,7 @@ Node ReifiedTripleSubject() : { Node s; String iri; } {
{ return s; }
}

// rtObject
// Turtle [31] -- rtObject ::= iri | BlankNode | literal | tripleTerm | reifiedTriple
Node ReifiedTripleObject() : { Node o; String iri; } {
( iri = iri() { o = createURI(iri, token.beginLine, token.beginColumn) ; }
| o = BlankNode()
Expand All @@ -390,6 +402,7 @@ Node ReifiedTripleObject() : { Node o; String iri; } {
{ return o; }
}

// Turtle [32] -- tripleTerm ::= '<<(' ttSubject verb ttObject ')>>'
Node TripleTerm() : { Node n = null ; Token openToken ; String iri ; Node s , p , o ; }
{
<L_TRIPLE>
Expand All @@ -400,7 +413,7 @@ Node TripleTerm() : { Node n = null ; Token openToken ; String iri ; Node s , p
{ return createTripleTerm(s, p, o, token.beginLine, token.beginColumn) ; }
}

// ttSubject
// Turtle [33] -- ttSubject ::= iri | BlankNode
Node TripleTermSubject(): { Node o ; String iri; }
{
( iri = iri() { o = createURI(iri, token.beginLine, token.beginColumn) ; }
Expand All @@ -409,7 +422,7 @@ Node TripleTermSubject(): { Node o ; String iri; }
{ return o; }
}

// ttObject
// Turtle [34] -- ttObject ::= iri | BlankNode | literal | tripleTerm
Node TripleTermObject(): { Node o ; String iri; }
{
( iri = iri() { o = createURI(iri, token.beginLine, token.beginColumn) ; }
Expand All @@ -421,6 +434,7 @@ Node TripleTermObject(): { Node o ; String iri; }
}

// RDF-star Annotation Syntax
// Turtle [35] -- annotation ::= (reifier | annotationBlock)*
void Annotation(Node s, Node p, Node o) : { Node reifId = null; }
{
(
Expand All @@ -434,17 +448,37 @@ void Annotation(Node s, Node p, Node o) : { Node reifId = null; }
) *
}

// Turtle [36] -- annotationBlock ::= '{|' predicateObjectList '|}'
void AnnotationBlock( Node reifId ) : {}
{
<L_ANN>
PredicateObjectList(reifId)
<R_ANN>
// (
// <L_ANN>
// { Node x = createQuotedTriple(s, p, o, token.beginLine, token.beginColumn); }
// PredicateObjectList(x)
// <R_ANN>
// )?
}

// ---- Turtle Terminals

// Turtle [38] -- IRIREF ::= ...
String IRIREF() : { Token t ; }
{
t = <IRIref>
{ return resolveQuotedIRI(t.image, t.beginLine, t.beginColumn) ; }
}

// Turtle [42] -- LANG_DIR ::= '@' [a-zA-Z]+ ('-' [a-zA-Z0-9]+)* ('--' [a-zA-Z]+)?
// modified to enumerate the @-directives here because they look like language tags.
String LangTag() : { Token t ; }
{
// Enumerate the directives here because they look like language tags.
( t = <LANG_DIR> | t = AnyAtDirective() )
{ String lang = stripChars(t.image, 1) ; return lang ; }
}

// @-directives are legal as language tags.
Token AnyAtDirective() : { Token t ; }
{
( t = <PREFIX_OLD> | t = <BASE_OLD> | t = <VERSION_OLD> )
{ return t ; }
}

// ------------------------------------------
Expand Down
Loading
Loading