Namespaced identifiers¶
is-ni¶
Description |
Examples |
|---|---|
Arguments:
VALUES(value-expression{1})
Boolean function that returns true if value is a namespaced
identifier literal, or if it is a list, that the first element
in the list is a namespaced identifier.
|
["is-ni", ["ni", "foo:bar"]]Returns
true.["is-ni", "foo:bar"]Returns
false.["is-ni", ["list", ["ni", "foo:bar"], 12345]]Returns
true.["is-ni", ["list", 1, ["ni", "foo:bar"]]]Returns
false. |
ni¶
Description |
Examples |
|---|---|
Arguments:
NAMESPACE(string{0|1}),
VALUES(value-expression{1})
Translates input values to namespaced identifiers. Strings and URIs in VALUES
will be cast to namespaced identifiers. Note that no escaping is done on
the strings.
If NAMESPACE is omitted, then the global namespace is used.
URIs can be passed as values in VALUES only when NAMESPACE is not specified.
The URIs will be collapsed, i.e. the prefix part of URIs will be collapsed into
a namespace. If the prefix has been declared as a namespace
then that namespace will be used, otherwise a generated namespace will be added.
|
Constructs a new namespaced identifier.
["ni", "foo", "bar"]This will produce a namespaced identifier
"~:foo:bar".["ni", "bar"]This will produce a namespaced identifier in the global namespace
"~:bar".["ni", "foo", ["list", "bar", "x:y"]]This will produce a list of two namespaced identifiers:
["~:foo:bar", "~:foo:x:y"].["ni", "foo", ["uri, "http://example.org/"]]Returns
null because URIs are not supported when NAMESPACE is specified.["ni", ["uri, "http://example.org/bar"]]Returns
"~:_:bar", i.e. a NI with the _ namespace and bar as identifier.
Note that the http://example.org/ URI prefix is mapped to the _ namespace
by default.["ni", ["uri, "http://unknown.org/something/baz"]]If the
"http://unknown.org/something/" URI prefix has not been declared as a
namespace then it will return "~:your-pipe-1:baz" if the current pipe id is
your-pipe. The -1 part is a sequence counter, so if you introduce other
namespaces in your pipe they’ll be assigned unique namespace ids. If the URI prefix
had already been mapped to the unknown namespace then the expression would have
returned "~:unknown:baz". |
ni-collapse¶
Description |
Examples |
|---|---|
Arguments:
VALUES(value-expression{1})
|
Uses the
namespaces.default service metadata contents to produce a namespaced identifier from URLs.
VALUES that are not URLs are ignored (i.e. it accepts strings and URI parameters). If there is no longest
matching prefix in the namespaces.default settings, the functions will return a NI that contains the
original input (i.e. the The http and https prefixes are implicitly defined). Non-http URIs are not
supported.
NOTE: this function is experimental and is meant to work with the global_defaults.symmetric_namespace_collapse
service metadata option set to true.Given this
namespaces.default mapping in the service metadata:{
"foo": "http://psi.test.no/",
"sesam_male": "http://sesam.io/people/male/",
"sesam_female": "http://sesam.io/people/female/",
"sesam": "http://sesam.io/people/"
}The following examples will produce this output:
["ni-collapse", "http://psi.test.no/bar"]Returns
"~:foo:bar".["ni-collapse", ["list", "http://psi.test.no/bar", "http://psi.test.no/baz"]]Returns
["~:foo:bar", "~:foo:baz"].["ni-collapse", "http://sesam.io/people/employees"]Returns
"~:sesam:employees".["ni-collapse", "http://sesam.io/people/male/john"]Returns
"~:sesam_male:john".["ni-collapse", "http://sesam.io/people/female/jane"]Returns
"~:sesam_female:jane".The
http and https namespaces are implicitly defined, so a URI that doesn’t match any prefix will work:["ni-collapse", "http://example.com/path"]Returns
"~:http://example.com/path". |
ni-expand¶
Description |
Examples |
|---|---|
Arguments:
VALUES(value-expression{1})
|
Uses the
namespaces.default service metadata contents to produce a URL string from a namespaced identifier.
VALUES that are not NIs are ignored. If there is no longest matching prefix in the namespaces.default
settings, the functions will return a string cast of the NI.
NOTE: this function is experimental and is meant to work with the global_defaults.symmetric_namespace_collapse
service metadata option set to true.Given this
namespaces.default mapping in the service metadata:{
"foo": "http://psi.test.no/",
"sesam_male": "http://sesam.io/people/male/",
"sesam_female": "http://sesam.io/people/female/",
"sesam": "http://sesam.io/people/"
}The following examples will produce this output:
["ni-expand", "~:foo:bar"]Returns
http://psi.test.no/bar.["ni-expand", ["list", "~:foo:bar", "~:foo:baz"]]Returns
["http://psi.test.no/bar", "http://psi.test.no/baz"].["ni-expand", "~:sesam:employees"]Returns
"http://sesam.io/people/employees".["ni-expand", "~:sesam_male:john"]Returns
"http://sesam.io/people/male/john".["ni-expand", "~:sesam_female:jane"]Returns
"http://sesam.io/people/female/jane".["ni-expand", "~:http://example.com/path"]Returns
"http://example.com/path".["ni-expand", "~:unknown:path"]Returns
"unknown:path". |
ni-id¶
Description |
Examples |
|---|---|
Arguments:
VALUES(value-expression{1})
|
Extracts the namespace id part of namespaced identifiers. VALUES that
are not namespaced identifiers or strings are ignored.
["ni-id", "~:foo:bar"]Returns
"bar".["ni-id", "foo:bar"]Returns
"bar".Returns
"bar".["ni-id", "bar"]Returns
"bar".["ni-id", ["list", "~:foo:bar", "~:bar:baz"]]Returns
["bar", "baz"].["ni-id", ["list", "foo:bar", "bar:baz"]]Returns
["bar", "baz"]. |
ni-ns¶
Description |
Examples |
|---|---|
Arguments:
VALUES(value-expression{1})
|
Extracts the namespace part of namespaced identifiers. VALUES that
are not namespaced identifiers or strings are ignored.
["ni-ns", "~:foo:bar"]Returns
"foo".["ni-ns", "foo:bar"]Returns
"foo".["ni-ns", "foo"]Returns
"".["ni-ns", ["list", "~:foo:bar", "~:bar:baz"]]Returns
["foo", "bar"].["ni-ns", ["list", "foo:bar", "bar:baz"]]Returns
["foo", "bar"]. |