e141841e78
- ability to create vocabulary namespaces from RDF data - XSD, RDF, RDFS, OWL and SKOS vocabulary namespaces
61 lines
1.9 KiB
Elixir
61 lines
1.9 KiB
Elixir
defmodule RDF.Namespace do
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@moduledoc """
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A `RDF.Namespace` is a module ...
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TODO: Rewrite this
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A `RDF.Namespace` is a collection of URIs and serves as a namespace for its
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elements, called terms. The terms can be accessed by qualification on the
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resp. namespace module.
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## Using a `RDF.Namespace`
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There are two types of terms in a `RDF.Namespace`, which are resolved
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differently:
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1. Lowercased terms (usually used for RDF properties, but this is not
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enforced) are represented as functions on a Vocabulary module and return the
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URI directly.
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2. Capitalized terms are by standard Elixir semantics modules names, i.e.
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atoms. In all places in RDF.ex, where an URI is expected, you can use atoms
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qualified with a `RDF.Namespace` directly, but if you want to resolve it
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manually, you can pass the `RDF.Namespace` qualified atom to `RDF.uri`.
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Examples:
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iex> RDF.NS.RDFS.subClassOf
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%URI{authority: "www.w3.org", fragment: "subClassOf", host: "www.w3.org",
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path: "/2000/01/rdf-schema", port: 80, query: nil, scheme: "http",
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userinfo: nil}
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iex> RDF.NS.RDFS.Class
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RDF.NS.RDFS.Class
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iex> RDF.uri(RDF.NS.RDFS.Class)
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%URI{authority: "www.w3.org", fragment: "Class", host: "www.w3.org",
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path: "/2000/01/rdf-schema", port: 80, query: nil, scheme: "http",
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userinfo: nil}
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iex> alias RDF.NS.RDFS
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iex> RDF.triple(RDFS.Class, RDFS.subClassOf, RDFS.Resource)
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{RDF.uri(RDFS.Class), RDF.uri(RDFS.subClassOf), RDF.uri(RDFS.Resource)}
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"""
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@callback __resolve_term__(atom) :: URI.t
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@callback __terms__() :: [atom]
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def resolve_term(expr)
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def resolve_term(uri = %URI{}), do: uri
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def resolve_term(namespaced_atom) when is_atom(namespaced_atom) do
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{term, namespace} =
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namespaced_atom
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|> Module.split
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|> List.pop_at(-1)
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{term, namespace} = {String.to_atom(term), Module.concat(namespace)}
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namespace.__resolve_term__(term)
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end
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end
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