Add namespaces and their prefixes as a named vector of URIs, with the
names being the prefixes. Namespaces have most relevance for meta objects'
rel
and property
, and for embedded XML literals.
Details
The implementation attempts to avoid duplication, currently using the
prefix. I.e., namespaces with prefixes already defined will not get added.
Namespaces needed by the NeXML format, and for commonly used metadata
terms, are already included by default, see get_namespaces()
.
Note
Often a user won't call this directly, but instead provide the
namespace(s) through add_meta()
.
Examples
## Write multiple metadata elements, including a new namespace:
website <- meta(href = "http://carlboettiger.info",
rel = "foaf:homepage") # meta can be link-style metadata
modified <- meta(property = "prism:modificationDate",
content = "2013-10-04")
nex <- add_meta(list(modified, website),
namespaces = c(foaf = "http://xmlns.com/foaf/0.1/"))
# prism prefix already included by default
## Add namespace "by hand" before adding meta:
nex <- add_namespaces(c(skos = "http://www.w3.org/2004/02/skos/core#"),
nexml = nex)
history <- meta(property = "skos:historyNote",
content = "Mapped from the bird.orders data in the ape package using RNeXML")
nex <- add_meta(history, nexml = nex)