36 lines
1.1 KiB
Elixir
36 lines
1.1 KiB
Elixir
defmodule RDF.NQuads.Encoder do
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@moduledoc false
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use RDF.Serialization.Encoder
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alias RDF.{Dataset, Graph, Quad, Statement, Triple}
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@impl RDF.Serialization.Encoder
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@callback encode(Graph.t | Dataset.t, keyword | map) :: {:ok, String.t} | {:error, any}
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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) -> [statement(statement) | result] 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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@spec statement({Statement.subject, Statement.predicate, Statement.object, nil}) :: String.t
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def statement({subject, predicate, object, nil}) do
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statement({subject, predicate, object})
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end
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@spec statement(Quad.t) :: String.t
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def statement({subject, predicate, object, graph}) do
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"#{term(subject)} #{term(predicate)} #{term(object)} #{term(graph)} ."
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end
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@spec statement(Triple.t) :: String.t
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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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defdelegate term(value), to: RDF.NTriples.Encoder
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end
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