librasqal(3)              OpenBSD Programmer's Manual             librasqal(3)



NAME
       librasqal - Rasqal RDF query library

SYNOPSIS
       #include <rasqal.h>

       rasqal_world*world=rasqal_new_world();
       rasqal_query_results *results;
       raptor_uri *base_uri=raptor_new_uri("http://example.org/foo");
       rasqal_query *rq=rasqal_new_query(world,"rdql",NULL);
       const char *query_string="select * from <http://example.org/data.rdf>";

       rasqal_query_prepare(rq,query_string,base_uri);
       results=rasqal_query_execute(rq);
       while(!rasqal_query_results_finished(results)) {
        for(i=0;i<rasqal_query_results_get_bindings_count(results);i++) {
         const char *name=rasqal_query_results_get_binding_name(results,i);
         rasqal_literal *value=rasqal_query_results_get_binding_value(results,i);
         /* ... */
        }
        rasqal_query_results_next(results);
       }
       rasqal_free_query_results(results);
       rasqal_free_query(rq);
       raptor_free_uri(base_uri);
       rasqal_free_world(world);

       cc `rasqal-config --cflags` file.c `rasqal-config --libs`

DESCRIPTION
       The Rasqal library provides a high-level interface to RDF query
       parsing, query construction, query execution over an RDF graph and
       query results manipulation and formatting.  The library provides APIs
       to each of the steps in the process and provides support for handling
       multiple query language syntaxes.  At present Rasqal partially supports
       the W3C draft SPARQL query language and fully supports RDQL.

       Rasqal uses the libraptor(3) library for providing URI handling, WWW
       content retrieval and other support functions.

LIBRARY INITIALISATION AND CLEANUP
       rasqal_world *rasqal_new_world(void)
              Create the rasqal world object.  This must be called before use
              of any rasqal library functions.

       void rasqal_free_world(rasqal_world* world)
              Destroy the rasqal world object and cleanup the library.  This
              must be called after destroying all rasqal objects.

LIBRARY FUNCTIONS
       These functions provide general library features not associated to any
       particular class.

       int rasqal_languages_enumerate(raptor_world* world, const unsigned int
       counter, const char **name, const char **label, const unsigned char
       **uri_string)
              Return the name, label, uri_string (all optional) for a query
              language with a given integer counter, returning non-zero if no
              such query language at that offset exists.  The counter should
              start from 0 and be incremented by 1 until the function returns
              non-zero.

       int rasqal_language_name_check(raptor_world* world, const char *name)
              Check name is a known query language name.

       int rasqal_query_set_feature(rasqal_query* query, rasqal_feature
       feature, int value)
              Set a query feature feature to a particular integer value.
              Returns non 0 on failure or if the feature is unknown.  The
              current defined parser features are:
                Feature                                 Values
                RASQAL_FEATURE_NO_NET                   Boolean (non 0 true)

       If the no_net feature is true (default false) then network requests are
       denied.

       int rasqal_query_set_feature_string(rasqal_query* query, rasqal_feature
       feature, const unsigned char* value)
              Set a query feature feature to a particular string value.
              Returns non 0 on failure or if the feature is unknown.  The
              current defined query features are given in
              rasqal_query_set_feature and at present only take integer
              values. If an integer value feature is set with this function,
              value is interpreted as an integer and then that value is used.

       int rasqal_query_get_feature(rasqal_query* query, rasqal_feature
       feature)
              Get a query feature integer value.  The allowed feature values
              and types are given under rasqal_features_enumerate.

       const unsigned char* rasqal_query_get_feature_string(rasqal_query*
       query, rasqal_feature feature)
              Get a query feature string value. The allowed feature values and
              types are given under rasqal_features_enumerate.

       int rasqal_features_enumerate(const rasqal_feature feature, const
       char** name, raptor_uri** uri, const char** label)
              Return the name, URI, string label (all optional) for a query
              feature, returning non-zero if no such feature exists.

       unsigned int rasqal_get_feature_count(void)
              Get the count of rasqal features defined which can be found with
              rasqal_features_enumerate.

       Rasqal features have URIs that are constructed from the URI
       http://feature.librdf.org/rasqal- and the name so for example feature
       noNet has URI http://feature.librdf.org/rasqal-noNet

       rasqal_feature rasqal_feature_from_uri(raptor_uri* uri)
              Turn a URI uri into a rasqal feature identifier, or <0 if the
              feature is unknown.  The URIs are described below
              rasqal_query_set_feature.

       int rasqal_feature_value_type(const rasqal_feature feature)
              Get a rasqal feature value tyype - integer or string.

QUERY CONSTRUCTOR
       rasqal_query* rasqal_new_query(raptor_world* world, const char *name,
       const unsigned char *uri)
              Create a new rasqal query object for the query syntax with name
              name.  Currently "rdql" for the RDF Data Query Language and
              "sparql" for the SPARQL query language are recognised.  A
              language may alternatively be identified by a URI uri.  If name
              and uri are both NULL the default query language is selected,
              currently "sparql".

QUERY DESTRUCTOR
       void rasqal_free_query(rasqal_query* query)
              Destroy a rasqal query object.

QUERY METHODS
       const char* rasqal_query_get_name(rasqal_query* query)
              Get the query language name.

       const char* rasqal_query_get_label(rasqal_query* query)
              Get the query language human readable label.

       void rasqal_query_set_fatal_error_handler(rasqal_query* query, void
       *user_data, raptor_message_handler handler)
              Set the fatal error handler callback.

       void rasqal_query_set_error_handler(rasqal_query* query, void
       *user_data, raptor_message_handler handler)
              Set the error handler callback.

       void rasqal_query_set_warning_handler(rasqal_query* query, void
       *user_data, raptor_message_handler handler)
              Set the warning handler callback.

       int rasqal_query_get_distinct(rasqal_query* query)
              Get the query distinct mode flag as described in
              rasqal_query_set_distinct()

       void rasqal_query_set_distinct(rasqal_query* query, int mode)
              Set the query distinct results mode: 0 (none), 1 (SPARQL
              DISTINCT) or 2 (SPARQL REDUCE).

       int rasqal_query_get_limit(rasqal_query* query)
              Get the query-specified limit on results returning >= 0 if a
              limit is given, otherwise not specified.

       void rasqal_query_set_limit(rasqal_query* query, int limit)
              Set the query results limit.  No more than limit results will be
              returned.

       int rasqal_query_get_offset(rasqal_query* query)
              Get the query-specified offset on results returning >= 0 if a
              offset is given, otherwise not specified.

       void rasqal_query_set_offset(rasqal_query* query, int offset)
              Set the query results offset.  The first offset results will be
              not be returned.

       int rasqal_query_add_variable(rasqal_query* query, rasqal_variable*
       var)
              Add a variable binding to the sequence of bindings in the query.

       raptor_sequence* rasqal_query_get_bound_variable_sequence(rasqal_query*
       query)
              Get the sequence of variables that are returning bindings in the
              query such as when explicitly chosen via SELECT in RDQL or
              SPARQL or all variables mentioned with SELECT *.

       raptor_sequence* rasqal_query_get_all_variable_sequence(rasqal_query*
       query)
              Get the sequence of all variables mentioned in the query.

       rasqal_variable* rasqal_query_get_variable(rasqal_query* query, int
       idx)
              Get one variable binding in the sequence of variable bindings in
              the query.

       raptor_sequence*
       rasqal_query_get_anonymous_variable_sequence(rasqal_query* query)
              Get the raptor_sequence of anonymous variables mentioned in the
              query.

       int rasqal_query_has_variable(rasqal_query* query, const unsigned char
       *name)
              Return non-0 if the named variable is in the variable bindings
              of the query.

       int rasqal_query_set_variable(rasqal_query* query, const unsigned char
       *name, rasqal_literal* value)
              Set the query variable name to a literal value (the variable
              must already be in the sequence of variable bindings).

       raptor_sequence* rasqal_query_get_triple_sequence(rasqal_query* query)
              Get the sequence of triples to match in the query.

       rasqal_triple* rasqal_query_get_triple(rasqal_query* query, int idx)
              Get one triple in the sequences of triples to match in the
              query.

       int rasqal_query_add_prefix(rasqal_query* query, rasqal_prefix* prefix)
              Add one namespace prefix/URI to the sequence of prefixes in the
              query.

       raptor_sequence* rasqal_query_get_prefix_sequence(rasqal_query* query)
              Get the sequence of prefixes in the query.

       rasqal_prefix* rasqal_query_get_prefix(rasqal_query* query, int idx)
              Get one prefix in the sequence of prefixes in the query at index
              idx.

       raptor_sequence* rasqal_query_get_graph_pattern_sequence(rasqal_query*
       query)
              Get the sequence of graph patterns expressions in the query.

       rasqal_graph_pattern* rasqal_query_get_graph_pattern(rasqal_query*
       query, int idx)
              Get a graph pattern in the sequence of graph_pattern expressions
              in the query.

       void rasqal_query_print(rasqal_query* query, FILE* stream)
              Print a query in a debug format.  This format may change in any
              release.

       int rasqal_query_prepare(rasqal_query* query, const unsigned char
       *query_string, raptor_uri *base_uri)
              Prepare a query string query_stringwith optional base URI
              uri_string for execution, parsing it and modifying the
              rasqal_query internals.  Return non-0 on failure.

       rasqal_query_results* rasqal_query_execute(rasqal_query* query)
              Execute a query, returning a rasqal_query_results* object or
              NULL on failure.

       void rasqal_query_set_user_data(rasqal_query* query, void *user_data)
              Set some user data to be associated with the query.

       void* rasqal_query_get_user_data(rasqal_query* query)
              Get the user data associated with the query.

       int rasqal_query_add_data_graph(rasqal_query* query, raptor_uri* uri,
       raptor_uri* name_uri, int flags)
              Add a data graph to the query's data sources, constructing a new
              data graph object with URI uri, optional name URI name_uri and
              flags.  See rasqal_new_data_graph for a description of the
              argumetns.

       raptor_sequence* rasqal_query_get_data_graph_sequence(rasqal_query*
       query)
              Get the sequence of data graphs in the query.

       rasqal_data_graph* rasqal_query_get_data_graph(rasqal_query* query, int
       idx)
              Get one prefix in the sequence of prefixes in the query at index
              idx.

       raptor_sequence*
       rasqal_query_get_order_conditions_sequence(rasqal_query* query)
              Get the sequence of all result ordering conditions in the query,
              each of which is a rasqal_expression.

       rasqal_expression* rasqal_query_get_order_condition(rasqal_query*
       query, int idx)
              Get one result ordering condition expression in the sequence.

       rasqal_query_verb rasqal_query_get_verb(rasqal_query* query)
              Get the main query verb.

       int rasqal_query_get_wildcard(rasqal_query* query)
              Get the query verb wildcard flag signifying * in RDQL and SPARQL
              after the query verb.

       rasqal_graph_pattern*
       rasqal_query_get_query_graph_pattern(rasqal_query* query)
              Get the top query graph pattern of query.

       void rasqal_query_set_default_generate_bnodeid_parameters(rasqal_query*
       rdf_query, char* prefix, int base)
              Control the default method for generation of IDs for blank
              nodes.  The method uses a short string prefix and an integer
              base to generate the identifier which is not guaranteed to be a
              strict concatenation.  If prefix is NULL, the default is used.
              If base is less than 1, it is initialised to 1.

       void rasqal_query_set_generate_bnodeid_handler(rasqal_query* query,
       void* user_data, rasqal_generate_bnodeid_handler handler)
              Allow full customisation of the generated IDs by setting a
              callback handler and associated user_data that is called
              whenever a blank node or bag identifier is required.  The memory
              returned is deallocated inside rasqal.  Some systems require
              this to be allocated inside the same library, in which case the
              rasqal_alloc_memory function may be useful.

       rasqal_query_verb_as_string(rasqal_query_verb verb)
              Get a string for the query verb.

       raptor_sequence*
       rasqal_query_get_construct_triples_sequence(rasqal_query* query)
              Get the sequence of triples for a construct.

       rasqal_triple* rasqal_query_get_construct_triple(rasqal_query* query,
       int idx)
              Get a triple in the sequence of construct triples.

       int rasqal_query_get_explain(rasqal_query* query)
              Get whether explain was given in the query.

       raptor_sequence*
       rasqal_query_get_group_conditions_sequence(rasqal_query* query)
              Get the sequence of result group bys in the graph pattern.

       rasqal_expression* rasqal_query_get_group_condition(rasqal_query*
       query, int idx)
              Get one group by expression in the sequences of result group bys
              in the graph pattern at index idx.

       int rasqal_query_write(raptor_iostream* iostr, rasqal_query* query,
       raptor_uri* format_uri, raptor_uri* base_uri)
              Write a formatted query to a raptor iostream iostr in format
              described by URI format_uri using base URI base_uri for relative
              URIs (or NULL).

       int rasqal_query_iostream_write_escaped_counted_string(rasqal_query*
       query, raptor_iostream* iostr, const unsigned char* string, size_t len)
              Write a string to an iostream in an escaped form suitable for
              the query string.  Uses rasqal_query_escape_counted_string to
              perform the escaping.

       unsigned char* rasqal_query_escape_counted_string(rasqal_query* query,
       const unsigned char *string, size_t len, size_t* output_len_p)
              Convert a string of length len into an escaped form suitable for
              the query string.  If output_len is not NULL, it is a pointer to
              the location to store the output string lenght.  The returned
              string must be freed by the caller with rasqal_free_memory.

GRAPH PATTERN CLASS
       A class for graph patterns in a query - a set of triple patterns) with
       flags and possible sub-graph patterns

GRAPH PATTERN CONSTRUCTOR
       There is no public constructor for this class, it is constructed when
       the query is prepared from a syntax. The query methods
       rasqal_query_get_graph_pattern_sequence and
       rasqal_query_get_graph_pattern provide access to the top-level graph
       patterns in a query.

       rasqal_triple* rasqal_graph_pattern_get_triple(rasqal_graph_pattern*
       graph_pattern, int idx)
              Get a rasqal_triple inside a graph pattern at index idx
              returning NULL when the index is out of range.

       int rasqal_graph_pattern_add_sub_graph_pattern(rasqal_graph_pattern*
       graph_pattern, rasqal_graph_pattern* sub_graph_pattern)
              Add a sub-graph pattern sub_graph_pattern to the sequence of
              sub-graph patterns inside the graph pattern.

       raptor_sequence*
       rasqal_graph_pattern_get_sub_graph_pattern_sequence(rasqal_graph_pattern*
       graph_pattern)
              Get the sequence of sub-graph patterns inside the graph pattern
              returning NULL if there are no sub-graph patterns.

       rasqal_graph_pattern*
       rasqal_graph_pattern_get_sub_graph_pattern(rasqal_graph_pattern*
       graph_pattern, int idx)
              Get a sub-graph pattern inside the graph pattern at index idx
              returning NULL when the index is out of range.

       rasqal_graph_pattern_operator
       rasqal_graph_pattern_get_operator(rasqal_graph_pattern* graph_pattern)
              Get the graph pattern operator to determine how the graph
              pattern should be interpreted.

       int rasqal_graph_pattern_add_constraint(rasqal_graph_pattern* gp,
       rasqal_expression* expr)
              Add a constraint expression expr to the sequence of constraints
              in the graph pattern.

       raptor_sequence*
       rasqal_graph_pattern_get_constraint_sequence(rasqal_graph_pattern* gp)
              Get the sequence of constraints in the graph pattern.

       rasqal_expression*
       rasqal_graph_pattern_get_constraint(rasqal_graph_pattern* gp, int idx)
              Get one constraint expression in the sequences of constraint to
              match in the graph pattern at index idx.

       int rasqal_graph_pattern_get_index(rasqal_graph_pattern* graph_pattern)
              Get the graph pattern absolute index in the array of graph
              patterns.  The index is assigned when rasqal_query_prepareP is
              run on the query containing the graph pattern.

       void rasqal_graph_pattern_print(rasqal_graph_pattern* graph_pattern,
       FILE* fh)
              Print a graph pattern in a debug format.  This format may change
              in any release.

       const char*
       rasqal_graph_pattern_operator_as_string(rasqal_graph_pattern_operator
       op)
              Utility function to get a graph pattern operator as a string.

       int rasqal_graph_pattern_visit(rasqal_graph_pattern* graph_pattern,
       rasqal_graph_pattern_visit_fn fn, void *user_data)
              Visit a user function fn recursively over the graph pattern and
              it's sub-graph patterns.  The order is the first graph pattern
              at hand and then the arguments, if any.  function fn is called
              at each point with the arguments of user_data and the graph
              pattern.

QUERY RESULTS CLASS
       A class for the results of a query.  The results can be in different
       formats - variable bindings, RDF graphs as a sequence of triples or a
       boolean result.  The format returned is determined by the query which
       is query-language specific.

QUERY RESULTS CONSTRUCTOR
       There is no public constructor for this class, the
       rasqal_query_results* is returned from rasqal_query_execute.

QUERY RESULTS DESTRUCTOR
       rasqal_free_query_results(rasqal_query_results *query_results)
              Destroy a rasqal query results object.

QUERY RESULTS METHODS
       int rasqal_query_results_is_bindings(rasqal_query_results*
       query_results)

       int rasqal_query_results_is_boolean(rasqal_query_results*
       query_results)

       int rasqal_query_results_is_graph(rasqal_query_results* query_results)

       int rasqal_query_results_is_syntax(rasqal_query_results*
       query_results);
              Return non-0 if the rasqal_query_results is of the given format.
              Only one of these will be non-0 for any result.

       int rasqal_query_results_read(raptor_iostream* iostr,
       rasqal_query_results* results, raptor_uri* format_uri, raptor_uri*
       base_uri)
              Read a query results in a syntax from the read iostr iostream,
              the format of the syntax is given by the format_uri URI, with an
              optional base URI base_uri that may be used.  The values of
              format_uri supported are provided by at runtime by the function
              rasqal_query_results_formats_enumerate().  This uses the
              librdf_query_results_formatter class internally.

       int rasqal_query_results_write(raptor_iostream *iostr,
       rasqal_query_results *results, raptor_uri *format_uri, raptor_uri
       *base_uri)
              Write the query results in a syntax to the write iostr iostream,
              the format of the syntax is given by the format_uri URI, with an
              optional base URI base_uri that may be used.  The values of
              format_uri supported are provided by at runtime by the function
              rasqal_query_results_formats_enumerate().  This uses the
              librdf_query_results_formatter class internally.

QUERY VARIABLE BINDINGS RESULTS METHODS
       int rasqal_query_results_get_count(rasqal_query_results *query_result)
              Get the current number of variable bindings results returned.
              (Variable bindings results only)

       int rasqal_query_results_next(rasqal_query_results *query_results)
              Move to the next variable bindings result, returning non-0 on
              failure or results are exhausted. (Variable bindings results
              only)

       int rasqal_query_results_finished(rasqal_query_results *query_results)
              Find out if the variable binding results are exhausted, return
              non-0 if results are finished or the query failed. (Variable
              bindings results only)

       int rasqal_query_results_get_bindings(rasqal_query_results
       *query_results, const unsigned char ***names, rasqal_literal ***values)
              Get all variable binding names and values for the current
              result.  If names is not NULL, it is set to the address of a
              shared array of names of the bindings (an output parameter).  If
              values is not NULL, it is set to the address of a shared array
              of rasqal_literal* binding values.  Note that both the names or
              values are shared and must not be freed by the caller.  Returns
              non-0 if the assignment failed. (Variable bindings results only)

       rasqal_literal*
       rasqal_query_results_get_binding_value(rasqal_query_results
       *query_results, int offset)
              Get one variable binding literal value for the current result.
              Returns the value of the variable indexed in the sequence of
              variable bindings at position offset. (Variable bindings results
              only)

       const unsigned char*
       rasqal_query_results_get_binding_name(rasqal_query_results
       *query_results, int offset)
              Get the name of the variable indexed in the sequence of variable
              bindings at position offset. (Variable bindings results only)

       rasqal_literal*
       rasqal_query_results_get_binding_value_by_name(rasqal_query_results
       *query_results, const unsigned char *name)
              Get the value of the variable in the sequence of variable
              bindings named name or NULL if not known or unbound. (Variable
              bindings results only)

       int rasqal_query_results_get_bindings_count(rasqal_query_results
       *query_results)
              Get the number of bound variables in the variable bindings
              result or <0 on failure. (Variable bindings results only)

QUERY BOOLEAN RESULTS METHODS
       int rasqal_query_results_get_boolean(rasqal_query_results
       *query_results)
              Return the value of a boolean query result.  This is meaningless
              if the query result is not a boolean. (Boolean result format
              only).

QUERY RDF GRAPH RESULTS METHODS
       raptor_statement* rasqal_query_results_get_triple(rasqal_query_results
       *query_results)
              Return the current triple in the RDF graph results or NULL at
              end of results or on failure.  The returned raptor_statement is
              a shared pointer.  (Graph results format only).

       int rasqal_query_results_next_triple(rasqal_query_results
       *query_results)
              Move to the next triple in the RDF graph results, returning
              non-0 at end of results or on failure. (Graph results format
              only).

QUERY RESULTS FORMATTER CLASS
       A class for formatting the results of a query into a syntax.

QUERY RESULTS FORMATTER CONSTRUCTOR
       rasqal_query_results_formatter*
       rasqal_new_query_results_formatter(raptor_world* world, const char
       *name, raptor_uri* uri)
              Create a new query results formatter for the name or uri.  The
              rasqal_query_results_formats_enumerate() function returns the
              allowed names and/or uris.  If name and uri are both NULL, the
              default query results format is used.

       rasqal_query_results_formatter*
       rasqal_new_query_results_formatter_by_mime_type(raptor_world* world,
       const char *mime_type)
              Create a new query results formatter for the output mime_type.
              The  rasqal_query_results_formats_enumerate_full() function
              returns the allowed names, uris and mime types.
              rasqal_query_results_formatter_get_mime_type() can return the
              mime type of a constructed object.

QUERY RESULTS FORMATTER DESTRUCTOR
       void
       rasqal_free_query_results_formatter(rasqal_query_results_formatter*
       formatter)
              Destroy a rasqal query results formatter object.

QUERY RESULTS FORMATTER METHODS
       int rasqal_query_results_formatter_read(rasqal_world* world,
       raptor_iostream* iostr, rasqal_query_results_formatter* formatter,
       rasqal_query_results* results, raptor_uri* base_uri)
              Read query results formatted in a syntax from the read iostr
              iostream with an optional base URI base_uri into results object.

       int rasqal_query_results_formatter_write(raptor_iostream* iostr,
       rasqal_query_results_formatter* formatter, rasqal_query_results*
       results, raptor_uri* base_uri)
              Write the query results formatted in a syntax to the iostr
              iostream an optional base URI base_uri.

       const char*
       rasqal_query_results_formatter_get_mime_type(rasqal_query_results_formatter*
       formatter)
              Get the mime type of the selected formatter.

QUERY RESULTS FORMATTER STATIC METHODS
       int rasqal_query_results_formats_enumerate(const unsigned int counter,
       const char **name, const char **label, const unsigned char
       **uri_string, const char **mime_type, int flags)
              Get query results formats information by counter..  When counter
              is 0, this returns the default query results format.  The name,
              label, uri_string and/or mime_type may be returned if they are
              not NULL.  Flags may be either
              RASQAL_QUERY_RESULTS_FORMAT_FLAG_READER or
              RASQAL_QUERY_RESULTS_FORMAT_FLAG_WRITER to return formats that
              can be read or written respectively.

       int rasqal_query_results_formats_check(raptor_world* world, const char
       *name, raptor_uri* uri, const char *mime_type)
              Check if a query results formatter with the given name, uri or
              mime_type exists, as would be used by the constructors
              rasqal_new_query_results_formatter() or
              rasqal_new_query_results_formatter_by_mime_type() if called.

LITERAL CLASS
       A class for the values returned as parts of triples and in variable
       bindings. The rasqal_literal structure is public and defined in
       rasqal.h however note that some fields are used for different literal
       types in different ways.  The types of literals are defined in the
       rasqal_literal_type enum.

LITERAL CONSTRUCTORS
       There a several constructors for rasqal_literal to build them from
       simple types and existing rasqal_literal objects.  NOTE: Any objects or
       strings passed into these constructors becomed owned by the literal
       object except where noted.

       rasqal_literal* rasqal_new_decimal_literal(raptor_world* world, const
       unsigned char* decimal)
              Create a new decimal literal from string decimal.

       rasqal_literal* rasqal_new_double_literal(raptor_world* world, double
       d)
              Create a new double literal from a d.

       rasqal_literal* rasqal_new_integer_literal(raptor_world* world,
       rasqal_literal_type type, int integer)
              Create a new integer literal of an integral type, either type
              RASQAL_LITERAL_INTEGER or RASQAL_LITERAL_BOOLEAN.

       rasqal_literal* rasqal_new_uri_literal(raptor_world* world, raptor_uri*
       uri)
              Create a new URI literal from a raptor_uri uri.

       rasqal_literal* rasqal_new_pattern_literal(raptor_world* world, const
       unsigned char *pattern, const char *flags)
              Create a new regular expression literal from regex pattern and
              flags.

       rasqal_literal* rasqal_new_string_literal(raptor_world* world, const
       unsigned char *string, const char *language, raptor_uri *datatype,
       const unsigned char *datatype_qname)
              Create a new Rasqal string literal.  The datatype and
              datatype_qname parameters are alternatives; the QName is a
              datatype that cannot be resolved till later since the prefixes
              have not yet been declared or checked at the time this
              constructor is called.

              If the string literal is datatyped and of certain types
              recognised (currently xsd:decimal, xsd:double) it may be
              internally converted to a different literal type.

       rasqal_literal* rasqal_new_simple_literal(raptor_world* world,
       rasqal_literal_type type, const unsigned char *string)
              Create a new Rasqal simple literal of type RASQAL_LITERAL_BLANK
              or RASQAL_LITERAL_BLANK_QNAME.

       rasqal_literal* rasqal_new_boolean_literal(raptor_world* world, int
       value)
              Create a new Raqal boolean literal, where value is non-0 for
              true, 0 for false.

       rasqal_literal* rasqal_new_variable_literal(raptor_world* world,
       rasqal_variable* variable)
              Create a new Rasqal variable literal using an existing variable
              object.

       rasqal_literal* rasqal_new_decimal_literal_from_decimal(raptor_world*
       world, const unsigned char *string, rasqal_xsd_decimal* decimal)
              Create a new Rasqal decimal literal using an existing string or
              decimal object.

       rasqal_literal* rasqal_new_float_literal(raptor_world* world, float f)
              Create a new Rasqal float literal using an existing foat f

       rasqal_literal* rasqal_new_typed_literal(raptor_world* world,
       rasqal_literal_type type, const unsigned char* string)
              Create a new Rasqal RDF typed literal of the given type and
              string form.

LITERAL COPY CONSTRUCTOR
       rasqal_literal* rasqal_new_literal_from_literal(rasqal_literal*
       literal)
              Copy an existing literal object.

LITERAL DESTRUCTOR
       void rasqal_free_literal(rasqal_uri* literal)
              Destroy a rasqal literal object.

LITERAL METHODS
       void rasqal_literal_print(rasqal_literal* literal, FILE* fh)
              Print a literal in a debug format.  This format may change in
              any release.

       rasqal_variable* rasqal_literal_as_variable(rasqal_literal* literal)
              Return a rasqal literal as a variable, if it is one, otherwise
              return NULL.

       const unsigned char* rasqal_literal_as_string(rasqal_literal* literal)
              Return a rasqal literal as a string value.  This always
              succeeds.

       const unsigned char* rasqal_literal_as_string_flags(rasqal_literal*
       literal, int flags, int* error)
              Return a rasqal literal as a string value according to flags.
              The only defined string value at present is
              RASQAL_COMPARE_XQUERY to use XQuery conversion rules.  If error
              is not NULL, it will be set to non-0 if there is an error.

       rasqal_literal* rasqal_literal_as_node(rasqal_literal* literal)
              Return a new rasqal literal into one suitable for a node in an
              RDF triple or binding - as a URI, literal string (or datatyped)
              or blank node.  The returned literal is owned by the caller and
              must be freed by rasqal_free_literal.

       int rasqal_literal_compare(rasqal_literal* literal1, rasqal_literal*
       literal2, rasqal_compare_flags flags, int* error)
              Compare two literals with type promotion across their range.  If
              the types are not the same, they are promoted.  If one is a
              floating, the other is promoted to floating, otherwise for
              integers, otherwise as strings (all literals have a string
              value).

              flags affects string comparisons.  If the RASQAL_COMPARE_NOCASE
              bit is set, a case independent comparison is made.

              The return value is comparable to strcmp(3), first before second
              returns <0.  equal returns 0, and first after second returns >0.
              If there is no ordering, such as for URIs, the return value is 0
              for equal, non-0 for different (using raptor_uri_equals).

       int rasqal_literal_equals(rasqal_literal* literal1, rasqal_literal*
       literal2)
              Compare two literals with no type promotion If literal2's value
              is a boolean, it will match
               the string "true" or "false" in literal1.

       rasqal_literal* rasqal_literal_value(rasqal_literal* literal)
              Get the value of a literal, looking up any variables.

       raptor_uri* rasqal_literal_datatype(rasqal_literal* literal)
              Get the datatype URI of a literal

TRIPLE CLASS
       A class for triples of three literals, used for matching triples in a
       query where the literals may be variables as well as in then interface
       between Rasqal and RDF systems using RDF triples, when the literals may
       not be literals.  The structure of this class is public and defined in
       rasqal.h

TRIPLE CONSTRUCTOR
       rasqal_triple* rasqal_new_triple(rasqal_literal* subject,
       rasqal_literal* predicate, rasqal_literal* object)
              Create a new rasqal triple from three literals.

TRIPLE COPY CONSTRUCTOR
       rasqal_triple* rasqal_new_triple_from_triple(rasqal_triple* triple)
              Copy an existing rasqal triple object.

TRIPLE DESTRUCTOR
       void rasqal_free_triple(rasqal_triple* triple)
              Destroy a rasqal triple object.

TRIPLE METHODS
       void rasqal_triple_print(rasqal_triple* triple, FILE* fh)
              Print a triple in a debug format.  This format may change in any
              release.

       void rasqal_triple_set_origin(rasqal_triple* triple, rasqal_literal
       *literal)
              Set the origin rasqal_literal of the triple, typically a URI
              literal.

       rasqal_literal* rasqal_triple_get_origin(rasqal_triple* triple)
              Get the origin rasqal_literal of the triple.

VARIABLE CLASS
       A class for variable name and literal used to capture a variable with
       optional value binding such as returned as query results by various
       methods.  The structure of this class is public and defined in rasqal.h

VARIABLE CONSTRUCTOR
       rasqal_variable* rasqal_new_variable(rasqal_query* query, const
       unsigned char *name, rasqal_literal* value)
              Create a new rasqal variable scoped to a Rasqal query, with
              required name and optional rasqal_literal value.  This creates a
              variable of type RASQAL_VARIABLE_TYPE_NORMAL.

       rasqal_variable* rasqal_new_variable_typed(rasqal_query* rq,
       rasqal_variable_type type, const unsigned char *name, rasqal_literal*
       value)
              Create a new rasqal variable scoped to a Rasqal query, with
              required name, optional rasqal_literal value and type type
              either RASQAL_VARIABLE_TYPE_NORMAL or
              RASQAL_VARIABLE_TYPE_ANONYMOUS

VARIABLE COPY CONSTRUCTOR
       rasqal_variable* rasqal_new_variable_from_variable(rasqal_variable*
       variable)
              Create a new rasqal variable object from an existing variable.

VARIABLE DESTRUCTOR
       void rasqal_free_variable(rasqal_variable* variable)
              Destroy a rasqal variable object.

VARIABLE METHODS
       void rasqal_variable_print(rasqal_variable* variable, FILE* fh)
              Print a variable in a debug format.  This format may change in
              any release.

       void rasqal_variable_set_value(rasqal_variable* variable,
       rasqal_literal* literal)
              Set the value of a rasqal variable to an rasqal_literal value,
              freeing any current value.  The new literal may be NULL.

PREFIX CLASS
       A class for namespace name/URI prefix association used to shorten URIs
       in some query languages using XML-style QNames.  The structure of this
       class is public and defined in rasqal.h

PREFIX CONSTRUCTOR
       rasqal_prefix* rasqal_new_prefix(const unsigned char* prefix,
       raptor_uri* uri)
              Create a new namespace prefix with the given short prefix and
              URI uri.

PREFIX DESTRUCTOR
       void rasqal_free_prefix(rasqal_prefix* prefix)
              Destroy a rasqal prefix object.

       void rasqal_prefix_print(rasqal_prefix* prefix, FILE* fh)
              Print a prefix in a debug format.  This format may change in any
              release.

EXPRESSION CLASS
       A class for constraint expressions over literals and variables.  The
       expression operators are defined in rasqal.h as enum rasqal_op and take
       one, two or more complex parameters.

EXPRESSION CONSTRUCTORS
       rasqal_expression* rasqal_new_0op_expression(rasqal_op op)
              Create a new expression with a 0-argument operator.

       rasqal_expression* rasqal_new_1op_expression(rasqal_op op,
       rasqal_expression* arg)
              Create a new expression with a 1-argument operator.

       rasqal_expression* rasqal_new_2op_expression(rasqal_op op,
       rasqal_expression* arg1, rasqal_expression* arg2)
              Create a new expression with a 2-argument operator.

       rasqal_expression* rasqal_new_2op_expression(rasqal_op op,
       rasqal_expression* arg1, rasqal_expression* arg2, rasqal_expression*
       arg3)
              Create a new expression with a 3-argument operator.

       rasqal_expression* rasqal_new_string_op_expression(rasqal_op op,
       rasqal_expression* arg1, rasqal_literal* literal)
              Create a new expression with a 2-argument operator, the second
              of which is a literal string.

       rasqal_expression* rasqal_new_literal_expression(rasqal_literal*
       literal)
              Create a new expression over an existing rasqal literal.

       rasqal_expression* rasqal_new_variable_expression(rasqal_variable*
       variable)
              Create a new expression over an existing rasqal variable.

       rasqal_expression* rasqal_new_function_expression(raptor_uri* name,
       raptor_sequence* args)
              Create a new expression for a function named name and with
              sequence of rasqal_literal* arguments args.

       rasqal_expression* rasqal_new_cast_expression(raptor_uri* name,
       rasqal_expression* value)
              Create a new expression for a casting of value to a datatype
              with URI name.

EXPRESSION COPY CONSTRUCTOR
       rasqal_expression*
       rasqal_new_expression_from_expression(rasqal_expression* expression)
              Copy an existing rasqal expression object.

EXPRESSION DESTRUCTOR
       void rasqal_free_expression(rasqal_expression* expression)
              Destroy a rasqal expression object.

EXPRESSION METHODS
       void rasqal_expression_print_op(rasqal_expression* expression, FILE*
       fh)
              Print an expression operator in a debug format.  This format may
              change in any release.

       void rasqal_expression_print(rasqal_expression* expression, FILE* fh)
              Print an expression in a debug format.  This format may change
              in any release.

       rasqal_literal* rasqal_expression_evaluate(rasqal_query* query,
       rasqal_expression* expression, rasqal_compare_flags flags)
              Evalute an expression, returning a rasqal boolean with the
              result or NULL on failure.  If flags are RASQAL_COMPARE_XQUERY
              then XQuery comparison and type promotions are used.

       int rasqal_expression_visit(rasqal_expression* expression,
       rasqal_expression_visit_fn fn, void *user_data)
              Visit a user function fn recursively over the expression and
              it's sub-expressions.  The order is the first expression at hand
              and then the arguments, if any.  function fn is called at each
              point with the arguments of user_data and the expression.

DATA GRAPH CLASS
       A class for graph data sources to query over from a source URI with an
       optional name URI.

DATA GRAPH CONSTRUCTOR
       rasqal_data_graph* rasqal_new_data_graph(raptor_uri* uri, raptor_uri*
       name_uri, int flags)
              Create a new data graph with source URI uri and optional name
              URI name_uri.  Flags can be RASQAL_DATA_GRAPH_NONE,
              RASQAL_DATA_GRAPH_NAMED or RASQAL_DATA_GRAPH_BACKGROUND.

DATA GRAPH DESTRUCTOR
       void rasqal_free_data_graph(rasqal_data_graph* dg)
              Destroy a rasqal data_graph object.

       void rasqal_data_graph_print(rasqal_data_graph* dg, FILE* fh)
              Print a data graph in a debug format.  This format may change in
              any release.

DECIMAL CLASS
       A class for accurate decimal arithmetic to handle XSD decimals.

DECIMAL CONSTRUCTOR
       rasqal_xsd_decimal* rasqal_new_xsd_decimal(void)
              Create a new decimal object.

DECIMAL DESTRUCTOR
       void rasqal_free_xsd_decimal(rasqal_xsd_decimal* dec)
              Destroy a rasqal decimal object.

DECIMAL METHODS
       int rasqal_xsd_decimal_set_string(rasqal_xsd_decimal* dec, const char*
       string)
              Set the decimal value from a string.

       double rasqal_xsd_decimal_get_double(rasqal_xsd_decimal* dec)
              Get the decimal value as a double - this may lose precision.

       char* rasqal_xsd_decimal_as_string(rasqal_xsd_decimal* dec)
              Get the decimal as a string.  The returned string is shared and
              must be copied by the caller.

       char* rasqal_xsd_decimal_as_counted_string(rasqal_xsd_decimal* dec,
       size_t* len_p)
              Get the decimal as a string plus optional length stored in len_p
              if it is not NULL .  The returned string is shared and must be
              copied by the caller.

       int rasqal_xsd_decimal_set_long(rasqal_xsd_decimal* dec, long l)
              Set the decimal value from a long.

       int rasqal_xsd_decimal_set_double(rasqal_xsd_decimal* dec, double d)
              Set the decimal value from a double.

       int rasqal_xsd_decimal_print(rasqal_xsd_decimal* dec, FILE* stream)
              Print the decimal to a FILE* stream.

       int rasqal_xsd_decimal_add(rasqal_xsd_decimal* result,
       rasqal_xsd_decimal* a, rasqal_xsd_decimal* b)
              Perform decimal a + b and store the result in result.

       int rasqal_xsd_decimal_subtract(rasqal_xsd_decimal* result,
       rasqal_xsd_decimal* a, rasqal_xsd_decimal* b)
              Perform decimal a - b and store the result in result.

       int rasqal_xsd_decimal_multiply(rasqal_xsd_decimal* result,
       rasqal_xsd_decimal* a, rasqal_xsd_decimal* b)
              Perform decimal a * b and store the result in result.

       int rasqal_xsd_decimal_divide(rasqal_xsd_decimal* result,
       rasqal_xsd_decimal* a, rasqal_xsd_decimal* b)
              Perform decimal a / b and store the result in result.

       int rasqal_xsd_decimal_negate(rasqal_xsd_decimal* result,
       rasqal_xsd_decimal* a)
              Perform decimal - a and store the result in result.

       int rasqal_xsd_decimal_compare(rasqal_xsd_decimal* a,
       rasqal_xsd_decimal* b)
              Compare decimal a to b and return <0, 0 or >0 if a is < b a = b
              or a > b in the same fashion as strcmp() does for strings.

       int rasqal_xsd_decimal_equals(rasqal_xsd_decimal* a,
       rasqal_xsd_decimal* b)
              Return non-0 if decimal a equals b.

       int rasqal_xsd_decimal_is_zero(rasqal_xsd_decimal* d)
              Return non-0 if decimal a is zero.

API CHANGES
   0.9.16
       Removed rasqal_init and rasqal_finish.

       Added a new rasqal_world object to manage library allocations and
       classes with constructor rasqal_new_world and destructor
       rasqal_free_world.

       The following functions now take a librdf_world* world argument as the
       first argument: rasqal_language_name_check, rasqal_languages_enumerate,
       rasqal_new_query, rasqal_query_results_formats_check ,
       rasqal_new_query_results_formatter,
       rasqal_new_query_results_formatter_by_mime_type,
       rasqal_new_integer_literal, rasqal_new_typed_literal,
       rasqal_new_double_literal, rasqal_new_float_literal,
       rasqal_new_uri_literal, rasqal_new_pattern_literal,
       rasqal_new_string_literal, rasqal_new_simple_literal,
       rasqal_new_boolean_literal, rasqal_new_variable_literal,
       rasqal_new_decimal_literal, rasqal_new_decimal_literal_from_decimal

       rasqal_query_add_variable, rasqal_query_add_prefix and
       rasqal_graph_pattern_add_sub_graph_pattern now have int return values
       for catchng allocation failure.

       Added rasqal_query_results_read

       Removed rasqal_query_results_formats_enumerate_full.

       rasqal_query_results_formats_enumerate gains a flags argument with
       values RASQAL_QUERY_RESULTS_FORMAT_FLAG_READER or
       RASQAL_QUERY_RESULTS_FORMAT_FLAG_WRITER

       Added rasqal_query_results_formatter_read

       Added rasqal_new_variable_from_variable

       The rasqal_triples_match struct now has a world field.

       Removed deprecated functions and macros: rasqal_new_floating_literal,
       rasqal_graph_pattern_get_flags and rasqal_expression_foreach functions,
       rasqal_expression_foreach_fn typedef and RASQAL_LITERAL_FLOATING macro

   0.9.15
       Added rasqal_xsd_decimal type and support functions
       rasqal_new_decimal_literal_from_decimal, rasqal_new_xsd_decimal,
       rasqal_free_xsd_decimal, rasqal_xsd_decimal_set_string,
       rasqal_xsd_decimal_get_double, rasqal_xsd_decimal_as_string,
       rasqal_xsd_decimal_as_counted_string, rasqal_xsd_decimal_set_long,
       rasqal_xsd_decimal_set_double, rasqal_xsd_decimal_print,
       rasqal_xsd_decimal_add, rasqal_xsd_decimal_subtract,
       rasqal_xsd_decimal_multiply, rasqal_xsd_decimal_divide,
       rasqal_xsd_decimal_negate, rasqal_xsd_decimal_compare,
       rasqal_xsd_decimal_equals and rasqal_xsd_decimal_is_zero

       Added RASQAL_EXPR_SAMETERM for SPARQL sameTerm

       Added rasqal_compare_flags RASQAL_COMPARE_RDF and RASQAL_COMPARE_URI.

       Added rasqal_new_typed_literal

       Added rasqal_new_float_literal

       Added rasqal_literal_datatype

       Added rasqal_literal_value

       Added rasqal_tripleparts RASQAL_TRIPLE_GRAPH, RASQAL_TRIPLE_SPO and
       RASQAL_TRIPLE_SPOG

   0.9.14
       Added rasqal_new_0op_expression.

       Added rasqal_new_query_results_formatter_by_mime_type and
       rasqal_query_results_formatter_get_mime_type.

       Added rasqal_query_results_formats_check and
       rasqal_query_results_formats_enumerate_full.

       Added 0y_results_is_syntax.

       Added query results group by accessor methods:
       rasqal_query_get_group_conditions_sequence and
       rasqal_query_get_group_condition for LAQRS.

       rasqal_query_set_distinct now takes a mode argument.

       Added new query verbs RASQAL_QUERY_VERB_DELETE and
       RASQAL_QUERY_VERB_INSERT for LAQRS.

       Added rasqal_query_get_explain

       rasqal_expression structure looses an unused field variable.

       Added rasqal_expression types RASQAL_EXPR_GROUP_COND_ASC,
       RASQAL_EXPR_GROUP_COND_DESC, RASQAL_EXPR_COUNT and RASQAL_EXPR_VARSTAR
       for LAQRS.

       rasqal_variable structure gains a new field expression for LAQRS..

       Added static variables rasqal_license_string and rasqal_home_url_string

   0.9.13
       Added rasqal_feature system with single feature RASQAL_FEATURE_NO_NET
       and functions rasqal_feature_from_uri, rasqal_feature_value_type,
       rasqal_features_enumerate, rasqal_get_feature_count,
       rasqal_query_get_feature, rasqal_query_get_feature_string,
       rasqal_query_set_feature and rasqal_query_set_feature_string.  int.

       Added rasqal_query_results_formatter class with constructor
       rasqal_new_query_results_formatter destructor
       rasqal_free_query_results_formatter and method
       rasqal_query_results_formatter_write.

       Added rasqal_query_results_formats_enumerate for listing supported
       formats.

   0.9.12
       Added rasqal_query_iostream_write_escaped_counted_string and
       rasqal_query_escape_counted_string

       Added rasqal_query_get_anonymous_variable_sequence

       Added rasqal_graph_pattern_get_index

       Added RASQAL_EXPR_REGEX to rasqal_op

       Added arg3 field to rasqal_expression for the REGEX operation.

       Added rasqal_query_write

       Added rasqal_new_3op_expression

       Added rasqal_literal_as_string_flags

   0.9.11
       Added enum rasqal_compare_flags flags for rasqal_expression_evaluate or
       rasqal_literal_compare.

       Function rasqal_expression_evaluate gains a flag argument.

       Added rasqal_expression_visit and type for visitor function
       rasqal_expression_visit_fn.

       Added rasqal_new_expression_from_expression.

       Deprecated rasqal_expression_foreach, replaced by
       rasqal_expression_visit.

       Remove unused rasqal_new_variable_expression prototype.

       Added rasqal_graph_pattern_visit and type for visitor function
       rasqal_graph_pattern_visit_fn.

       Added rasqal_new_decimal_literal.

       Deprecated rasqal_new_floating_literal replaced by new
       rasqal_new_double_literal.

       Added rasqal_op type RASQAL_EXPR_LANGMATCHES for SPARQL langMatches().

       Added rasqal_literal types: RASQAL_LITERAL_DECIMAL,
       RASQAL_LITERAL_DATETIME, RASQAL_LITERAL_DOUBLE (replacing deprecated
       RASQAL_LITERAL_FLOATING) and RASQAL_LITERAL_FLOAT.

       Reordered the rasqal_literal types in the enum.

   0.9.10
       Added an rasqal_graph_pattern_operator enumerated type.  with the
       following (useful) values: RASQAL_GRAPH_PATTERN_OPERATOR_BASIC (for
       triple patterns), RASQAL_GRAPH_PATTERN_OPERATOR_OPTIONAL (for SPARQL
       OPTIONAL), RASQAL_GRAPH_PATTERN_OPERATOR_UNION,
       RASQAL_GRAPH_PATTERN_OPERATOR_GROUP and
       RASQAL_GRAPH_PATTERN_OPERATOR_GRAPH (for SPARQL GRAPH).

       Added graph pattern method rasqal_graph_pattern_get_operator Deprecated
       rasqal_graph_pattern_get_flags replaced by the above.  Added helper
       function rasqal_graph_pattern_operator_as_string.

       Modified the type of the final argument of
       rasqal_new_graph_pattern_from_sequence and
       rasqal_graph_pattern_add_triples from an integer to a
       rasqal_graph_pattern_operator enumeration.

       Removed documentation of removed functions deprecated in 0.9.9.

   0.9.9
       Added query methods rasqal_query_get_construct_triple,
       rasqal_query_get_construct_triples_sequence, rasqal_query_get_offset,
       rasqal_query_get_order_condition,
       rasqal_query_get_order_conditions_sequence,
       rasqal_query_get_query_graph_pattern, rasqal_query_get_verb,
       rasqal_query_get_wildcard.
       rasqal_query_set_default_generate_bnodeid_parameters,
       rasqal_query_set_distinct, rasqal_query_set_generate_bnodeid_handler,
       rasqal_query_set_limit and rasqal_query_set_offset.

       Added expressions RASQAL_EXPR_ORDER_COND_ASC,
       RASQAL_EXPR_ORDER_COND_DESC and RASQAL_EXPR_ORDER_COND_NONE.

       Added enum rasqal_variable_type for typing variables.

       Added variable constructor rasqal_new_variable_typed to create typed
       variables.

       Added enum rasqal_query_verb for the main query verbs with values
       RASQAL_QUERY_VERB_SELECT, RASQAL_QUERY_VERB_CONSTRUCT
       RASQAL_QUERY_VERB_DESCRIBE and RASQAL_QUERY_VERB_ASK.

       Added rasqal_query_verb_as_string to get a strign for a query verb.

       Deprecated the rasqal_triple flags field and the triple methods
       rasqal_triple_set_flags and rasqal_triple_get_flags.

   0.9.8
       Added a Data Graph class with constructor rasqal_new_data_graph,
       destructor rasqal_free_data_graph and debug method
       rasqal_data_graph_print.

       Added casting expressions with type RASQAL_EXPR_CAST and expression
       constructor rasqal_new_cast_expression

       Added a no-arg graph pattern constructor rasqal_new_graph_pattern

       Added graph pattern methods rasqal_graph_pattern_add_triples to add
       triples to a graph pattern and
       rasqal_graph_pattern_add_sub_graph_pattern to add a sub-graph pattern
       to a graph pattern.

       Added graph pattern methods rasqal_graph_pattern_add_constraint,
       rasqal_graph_pattern_get_constraint_sequence and
       rasqal_graph_pattern_get_constraint to add constraints to a graph
       pattern.

       Added query methods for data graphs: rasqal_query_add_data_graph,
       rasqal_query_get_data_graph_sequence, rasqal_query_get_data_graph.

       Deprecated query methods: rasqal_query_add_constraint,
       rasqal_query_get_constraint_sequence rasqal_query_get_constraint,
       rasqal_query_add_source, rasqal_query_get_source_sequence and
       rasqal_query_get_source.

       Removed deprecated query methods: rasqal_query_get_variable_sequence
       and rasqal_query_add_triple.

   0.9.7
       Export rasqal_graph_pattern typedef for graph patterns and added access
       methods: rasqal_query_get_graph_pattern_sequence
       rasqal_query_get_graph_pattern, rasqal_graph_pattern_get_triple,
       rasqal_graph_pattern_get_sub_graph_pattern_sequence,
       rasqal_graph_pattern_get_sub_graph_pattern,
       rasqal_graph_pattern_get_flags
        and exported previously internal rasqal_graph_pattern_print Export
       rasqal_pattern_flags enum for graph pattern flags.

       Added rasqal_query_get_bound_variable_sequence and
       rasqal_query_get_all_variable_sequence.

       Deprecate rasqal_query_get_variable_sequence prefering
       rasqal_query_get_bound_variable_sequence

       Added  rasqal_query_get_distinct and rasqal_query_get_limit to get
       access to query flags.

       Deleted RASQAL_EXPR_PATTERN which was never used.

   0.9.6
       Added new 1-argument expressions to the expression constructor;
       rasqal_op enum gained the following values: RASQAL_EXPR_LANG,
       RASQAL_EXPR_DATATYPE, RASQAL_EXPR_BOUND, RASQAL_EXPR_ISURI,
       RASQAL_EXPR_ISBLANK and RASQAL_EXPR_ISLITERAL

       Added user-defined function expressions to the expression constructor:
       rasqal_op enum gained RASQAL_EXPR_FUNCTION value; rasqal_expression
       gained name and args fields and added rasqal_new_function_expression to
       construct a function expression.

       Added rasqal_query_results_is_bindings, rasqal_query_results_is_boolean
       and rasqal_query_results_is_graph to test the format of query result.

       Added rasqal_query_results_get_boolean to get the value of a boolean
       query result.

       Added rasqal_query_results_get_triple and
       rasqal_query_results_next_triple to return an RDF graph query result.

       Added rasqal_new_triple_from_triple triple copy constructor.

   0.9.5
       Added rasqal_query_results_write to format query results into a syntax,
       written to a raptor iostream.

       Changed rasqal_new_floating_literal to take a double argument.

       Added flags for triples with rasqal_triple_get_flags and
       rasqal_triple_set_flags to get and set them.

       Added rasqal_triple_parts enum and updated the bind_match factory
       method of the rasqal_triples_match structure to take and return them.

       Added a rasqal_triple_parts type field parts to the rasqal_triple_meta
       structure

   0.9.4
       No API changes.

   0.9.3
       The struct rasqal_prefix gained a declared field.

       The struct rasqal_triple gained an origin field; not used at present
       but intended to support work on tracking triple provenance such as
       provided by Redland Contexts.

       Added methods rasqal_triple_set_origin and rasqal_triple_get_origin to
       support the above.

       struct rasqal_triple_meta now takes a 4-array of bindings, the fourth
       being the origin.

       Exported function rasqal_set_triples_source_factory publically as
       intended.

   0.9.2
       Several functions changed their parameters or return values from char*
       to unsigned char* or const unsigned char* to reflect the actual use.

       Changed to return a const unsigned char*:
       rasqal_literal_as_string

       Changed to take const unsigned char* (or add const):
       rasqal_new_floating_literal
       rasqal_new_pattern_literal
       rasqal_new_prefix
       rasqal_new_simple_literal
       rasqal_new_string_literal
       rasqal_new_variable
       rasqal_query_has_variable
       rasqal_query_results_get_binding_name
       rasqal_query_results_get_binding_value_by_name
       rasqal_query_results_get_bindings
       rasqal_query_set_variable

   0.9.1
       Added the rasqal_query_results class and moved the results methods from
       rasqal_query.

       Made rasqal_query_execute return a rasqal_query_result*.

       Renamed all rasqal_query*result* methods to be rasqal_query_result_*
       Added rasqal_free_query_results to tidy up.

       OLD API (0.9.0)                          NEW API (0.9.1+)
       rasqal_query_get_result_count            rasqal_query_results_get_count
       rasqal_query_next_result                 rasqal_query_results_next
       rasqal_query_results_finished            rasqal_query_results_finished
       rasqal_query_get_result_bindings         rasqal_query_results_get_bindings
       rasqal_query_get_result_binding_value    rasqal_query_results_get_binding_value
       rasqal_query_get_result_binding_name     rasqal_query_results_get_binding_name
       rasqal_query_get_result_binding_by_name  rasqal_query_results_get_binding_value_by_name
       rasqal_query_get_bindings_count          rasqal_query_results_get_bindings_count

   0.9.0
       All new.

CONFORMING TO
       SPARQL Query Language for RDF, Eric Prud'hommeaux and Andy Seaborne
       (eds), W3C Recommendation, 15 January 2008
       http://www.w3.org/TR/2008/REC-rdf-sparql-query-20080115/
       <http://www.w3.org/TR/2008/REC-rdf-sparql-query-20080115/>

       SPARQL Query Results XML Format, Jeen Broekstra and Dave Beckett (eds),
       W3C Recommendation, 15 January 2008.  http://www.w3.org/TR/2008/REC-
       rdf-sparql-XMLres-20080115/ <http://www.w3.org/TR/2008/REC-rdf-sparql-
       XMLres-20080115/>

       RDQL - A Query Language for RDF, Andy Seaborne, W3C Member Submission 9
       January 2004 http://www.w3.org/Submission/2004/SUBM-RDQL-20040109/
       <http://www.w3.org/Submission/2004/SUBM-RDQL-20040109/>

SEE ALSO
       roqet(1),rasqal-config(1)

AUTHOR
       Dave Beckett - http://purl.org/net/dajobe/
       <http://purl.org/net/dajobe/>



                                  2008-06-22                      librasqal(3)
