49 lines
1.1 KiB
Elixir
49 lines
1.1 KiB
Elixir
defmodule RDF.NTriples.Encoder do
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@moduledoc false
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use RDF.Serialization.Encoder
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alias RDF.{Literal, BlankNode}
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@xsd_string RDF.Datatype.NS.XSD.string
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def encode(data, opts \\ []) do
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result =
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data
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|> Enum.reduce([], fn (statement, result) ->
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[statement(statement) | result]
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end)
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|> Enum.reverse
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|> Enum.join("\n")
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{:ok, (if result == "", do: result, else: result <> "\n")}
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end
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def statement({subject, predicate, object}) do
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"#{term(subject)} #{term(predicate)} #{term(object)} ."
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end
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def term(%URI{} = uri) do
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"<#{to_string(uri)}>"
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end
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def term(%Literal{value: value, language: language}) when not is_nil(language) do
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~s["#{value}"@#{language}]
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end
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def term(%Literal{value: value, language: language}) when not is_nil(language) do
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~s["#{value}"@#{language}]
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end
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def term(%Literal{datatype: @xsd_string} = literal) do
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~s["#{Literal.lexical(literal)}"]
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end
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def term(%Literal{datatype: datatype} = literal) do
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~s["#{Literal.lexical(literal)}"^^<#{to_string(datatype)}>]
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end
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def term(%BlankNode{} = bnode) do
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to_string(bnode)
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end
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end
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