public BooleanExpression IsLiteral(SparqlExpression term)
{
var isLiteral = new IsLiteralFunction(term.Expression);
return(new BooleanExpression(isLiteral));
}
/// <summary>
/// Tries to create a SPARQL Function expression if the function Uri correseponds to a supported SPARQL Function.
/// </summary>
/// <param name="u">Function Uri.</param>
/// <param name="args">Function Arguments.</param>
/// <param name="scalarArguments">Scalar Arguments.</param>
/// <param name="expr">Generated Expression.</param>
/// <returns>Whether an expression was successfully generated.</returns>
public bool TryCreateExpression(Uri u, List <ISparqlExpression> args, Dictionary <string, ISparqlExpression> scalarArguments, out ISparqlExpression expr)
{
String func = u.ToString();
if (func.StartsWith(SparqlFunctionsNamespace))
{
func = func.Substring(SparqlFunctionsNamespace.Length);
func = func.ToUpper();
// If any Scalar Arguments are present then can't be a SPARQL Function UNLESS it is
// a GROUP_CONCAT function and it has the SEPARATOR argument
if (scalarArguments.Count > 0)
{
if (func.Equals(SparqlSpecsHelper.SparqlKeywordGroupConcat) && scalarArguments.Count == 1 && scalarArguments.ContainsKey(SparqlSpecsHelper.SparqlKeywordSeparator))
{
// OK
}
else
{
expr = null;
return(false);
}
}
// Q: Will there be special URIs for the DISTINCT modified forms of aggregates?
ISparqlExpression sparqlFunc = null;
switch (func)
{
case SparqlSpecsHelper.SparqlKeywordAbs:
if (args.Count == 1)
{
sparqlFunc = new AbsFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ABS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordAvg:
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new AverageAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL AVG() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordBound:
if (args.Count == 1)
{
if (args[0] is VariableTerm)
{
sparqlFunc = new BoundFunction((VariableTerm)args[0]);
}
else
{
throw new RdfParseException("The SPARQL BOUND() function only operates over Variables");
}
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL BOUND() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordCeil:
if (args.Count == 1)
{
sparqlFunc = new CeilFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL CEIL() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordCoalesce:
if (args.Count >= 1)
{
sparqlFunc = new CoalesceFunction(args);
}
else
{
throw new RdfParseException("The SPARQL COALESCE() function requires at least 1 argument");
}
break;
case SparqlSpecsHelper.SparqlKeywordConcat:
if (args.Count >= 1)
{
sparqlFunc = new ConcatFunction(args);
}
else
{
throw new RdfParseException("The SPARQL CONCAT() function requires at least 1 argument");
}
break;
case SparqlSpecsHelper.SparqlKeywordContains:
if (args.Count == 2)
{
sparqlFunc = new ContainsFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL CONTAINS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordCount:
// Q: What will the URIs be for the special forms of COUNT?
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new CountAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL COUNT() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordDataType:
if (args.Count == 1)
{
sparqlFunc = new DataTypeFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL DATATYPE() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordDay:
if (args.Count == 1)
{
sparqlFunc = new DayFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL DAY() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordEncodeForUri:
if (args.Count == 1)
{
sparqlFunc = new EncodeForUriFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ENCODE_FOR_URI() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordFloor:
if (args.Count == 1)
{
sparqlFunc = new FloorFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL FLOOR() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordGroupConcat:
if (args.Count == 1)
{
if (scalarArguments.ContainsKey(SparqlSpecsHelper.SparqlKeywordSeparator))
{
sparqlFunc = new AggregateTerm(new GroupConcatAggregate(args.First(), scalarArguments[SparqlSpecsHelper.SparqlKeywordSeparator]));
}
else
{
sparqlFunc = new AggregateTerm(new GroupConcatAggregate(args.First()));
}
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL GROUP_CONCAT() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordHours:
if (args.Count == 1)
{
sparqlFunc = new HoursFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL HOURS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIf:
if (args.Count == 3)
{
sparqlFunc = new IfElseFunction(args[0], args[1], args[2]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL IF() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIri:
if (args.Count == 1)
{
sparqlFunc = new IriFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL IRI() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIsBlank:
if (args.Count == 1)
{
sparqlFunc = new IsBlankFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ISBLANK() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIsIri:
if (args.Count == 1)
{
sparqlFunc = new IsIriFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ISIRI() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIsLiteral:
if (args.Count == 1)
{
sparqlFunc = new IsLiteralFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ISLITERAL() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIsNumeric:
if (args.Count == 1)
{
sparqlFunc = new IsNumericFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ISNUMERIC() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordIsUri:
if (args.Count == 1)
{
sparqlFunc = new IsUriFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ISURI() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordLang:
if (args.Count == 1)
{
sparqlFunc = new LangFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL LANG() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordLangMatches:
if (args.Count == 2)
{
sparqlFunc = new LangMatchesFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL LANGMATCHES() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordLCase:
if (args.Count == 1)
{
sparqlFunc = new LCaseFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL LCASE() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordMax:
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new MaxAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL MAX() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordMD5:
if (args.Count == 1)
{
sparqlFunc = new MD5HashFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL MD5() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordMin:
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new MinAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL MIN() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordMinutes:
if (args.Count == 1)
{
sparqlFunc = new MinutesFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL MINUTES() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordMonth:
if (args.Count == 1)
{
sparqlFunc = new MonthFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL MONTH() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordNow:
if (args.Count == 0)
{
sparqlFunc = new NowFunction();
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ABS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordRegex:
if (args.Count == 2)
{
sparqlFunc = new RegexFunction(args[0], args[1]);
}
else if (args.Count == 3)
{
sparqlFunc = new RegexFunction(args[0], args[1], args[2]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL REGEX() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordRound:
if (args.Count == 1)
{
sparqlFunc = new RoundFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL ROUND() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSameTerm:
if (args.Count == 2)
{
sparqlFunc = new SameTermFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SAMETERM() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSample:
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new SampleAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL AVG() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordSeconds:
if (args.Count == 1)
{
sparqlFunc = new SecondsFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SECONDS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSha1:
if (args.Count == 1)
{
sparqlFunc = new Sha1HashFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SHA1() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSha256:
if (args.Count == 1)
{
sparqlFunc = new Sha256HashFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SHA256() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSha384:
if (args.Count == 1)
{
sparqlFunc = new Sha384HashFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SHA384() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSha512:
if (args.Count == 1)
{
sparqlFunc = new Sha512HashFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SHA512() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStr:
if (args.Count == 1)
{
sparqlFunc = new StrFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STR() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStrDt:
if (args.Count == 2)
{
sparqlFunc = new StrDtFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STRDT() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStrEnds:
if (args.Count == 2)
{
sparqlFunc = new StrEndsFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STRENDS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStrLang:
if (args.Count == 2)
{
sparqlFunc = new StrLangFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STRLANG() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStrLen:
if (args.Count == 1)
{
sparqlFunc = new StrLenFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STRKEN() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordStrStarts:
if (args.Count == 2)
{
sparqlFunc = new StrStartsFunction(args[0], args[1]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL STRSTARTS() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSubStr:
if (args.Count == 2)
{
sparqlFunc = new SubStrFunction(args[0], args[1]);
}
else if (args.Count == 3)
{
sparqlFunc = new SubStrFunction(args[0], args[1], args[2]);
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SUBSTR() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordSum:
if (args.Count == 1)
{
sparqlFunc = new AggregateTerm(new SumAggregate(args.First()));
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL SUM() aggregate");
}
break;
case SparqlSpecsHelper.SparqlKeywordTimezone:
if (args.Count == 1)
{
sparqlFunc = new TimezoneFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL TIMEZONE() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordTz:
if (args.Count == 1)
{
sparqlFunc = new TZFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL TZ() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordUCase:
if (args.Count == 1)
{
sparqlFunc = new UCaseFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL UCASE() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordUri:
if (args.Count == 1)
{
sparqlFunc = new IriFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL URI() function");
}
break;
case SparqlSpecsHelper.SparqlKeywordYear:
if (args.Count == 1)
{
sparqlFunc = new YearFunction(args.First());
}
else
{
throw new RdfParseException("Incorrect number of arguments for the SPARQL YEAR() function");
}
break;
}
if (sparqlFunc != null)
{
expr = sparqlFunc;
return(true);
}
}
expr = null;
return(false);
}
/// <summary>
/// Creates a call to the isLiteral function with an expression parameter
/// </summary>
/// <param name="eb"> </param>
/// <param name="term">any SPARQL expression</param>
public static BooleanExpression IsLiteral(this ExpressionBuilder eb, SparqlExpression term)
{
var isLiteral = new IsLiteralFunction(term.Expression);
return(new BooleanExpression(isLiteral));
}