triple#

A subject-predicate-object triple type.

This library defines triples as subject-predicate-object tuplets with an id. This allow a allows the subject or object to refer to another triple via its id, as one would expect for RDF triples (see https://en.wikipedia.org/wiki/Semantic_triple).

Typedefs

typedef struct _Triple Triple#: A subject-predicate-object triple used to represent a relation. The s-p-o-id strings should be allocated with malloc.

Functions

void triple_set_default_namespace(const char *namespace)#

Sets default namespace to be prepended to triple id’s.

Use this function to convert the id’s to proper URI’s.

const char *triple_get_default_namespace(void)#: Returns default namespace.

void triple_clean(Triple *t)#: Frees up memory used by the s-p-o strings, but not the triple itself.

int triple_set(Triple *t, const char *s, const char *p, const char *o, const char *d, const char *id)#: Convinient function to assign a triple. This allocates new memory for the internal s, p, o and id pointers. If id is NULL, a new id will be generated bases on s, p and o. For literals, the datatype can be provided with d.

int triple_reset(Triple *t, const char *s, const char *p, const char *o, const char *d, const char *id)#: Like triple_set(), but free’s allocated memory in t before re-assigning it. Don’t use this function if t has not been initiated.

char *triple_get_id(const char *namespace, const char *s, const char *p, const char *o, const char *d)#

Returns an newly malloc’ed unique id calculated from triple.

If namespace is NULL, the default namespace set with triple_set_default_namespace() will be used.

Returns NULL on error.

Triple *triple_copy(Triple *dest, const Triple *src)#

Copies triple src to dest and returns a pointer to dest.

Existing memory hold by dest is not free’ed. So if dest may hold some memory, call triple_clean() before calling this function.

struct _Triple#

#include <triple.h>

A subject-predicate-object triple used to represent a relation. The s-p-o-id strings should be allocated with malloc.

Public Members

char *s#: subject

char *p#: predicate

char *o#: object

char *d#: datatype

char *id#: unique ID identifying this triple