RDF.ex v0.7.1 RDF.Datatype behaviour View Source

A behaviour for natively supported literal datatypes.

A RDF.Datatype implements the foundational functions for the lexical form, the validation, conversion and canonicalization of typed RDF.Literals.

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Functions

Returns the RDF.Datatype for a directly datatype IRI or the datatype IRI of a RDF.Literal.

The IRIs of all datatypes with a RDF.Datatype defined.

The mapping of IRIs of datatypes to their RDF.Datatype.

All defined RDF.Datatype modules.

Callbacks

Produces the canonical form of a RDF.Literal.

Produces the lexical form of a value.

Casts a literal of another datatype into a literal of the datatype the function is implemented on.

Converts a value into a proper native value.

Checks if the value of two RDF.Literals of this datatype are equal.

The IRI of the datatype.

Produces the lexical form of an invalid value of a typed Literal.

Produces the lexical form of a RDF.Literal.

Determines if the value of a RDF.Literal is a member of lexical value space of its datatype.

Link to this section Types

Link to this section Functions

Returns the RDF.Datatype for a directly datatype IRI or the datatype IRI of a RDF.Literal.

The IRIs of all datatypes with a RDF.Datatype defined.

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mapping()

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mapping() :: %{required(RDF.IRI.t()) => t()}

The mapping of IRIs of datatypes to their RDF.Datatype.

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modules()

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modules() :: [t()]

All defined RDF.Datatype modules.

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Produces the canonical form of a RDF.Literal.

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canonical_lexical(arg1)

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canonical_lexical(RDF.Literal.literal_value()) :: String.t() | nil

Produces the lexical form of a value.

Casts a literal of another datatype into a literal of the datatype the function is implemented on.

If the given literal is invalid or can not be converted into this datatype nil is returned.

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compare(arg1, arg2)

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compare(RDF.Literal.t(), RDF.Literal.t()) ::
  :lt | :gt | :eq | :indeterminate | nil

Compares two RDF.Literals.

Returns :gt if first literal is greater than the second in terms of their datatype and :lt for vice versa. If the two literals are equal :eq is returned. For datatypes with only partial ordering :indeterminate is returned when the order of the given literals is not defined.

Returns nil when the given arguments are not comparable datatypes or if one them is invalid.

The default implementation of the _using__ macro compares the values of the canonical/1 forms of the given literals of this datatype.

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convert(any, map)

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convert(any(), map()) :: any()

Converts a value into a proper native value.

If an invalid value is given an implementation should call super, which by default currently just returns nil.

Note: If a value is valid is determined by the lexical space of the implemented datatype, not by the Elixir semantics. For example, although 42 is a falsy value according to the Elixir semantics, this is not an element of the lexical value space of an xsd:boolean, so the RDF.Boolean implementation of this datatype calls super.

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equal_value?(arg1, arg2)

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equal_value?(RDF.Literal.t(), RDF.Literal.t()) :: boolean() | nil

Checks if the value of two RDF.Literals of this datatype are equal.

Non-RDF terms are tried to be coerced via RDF.Term.coerce/1 before comparison.

Returns nil when the given arguments are not comparable as literals of this datatype.

The default implementation of the _using__ macro compares the values of the canonical/1 forms of the given literals of this datatype.

The IRI of the datatype.

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invalid_lexical(any)

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invalid_lexical(any()) :: String.t() | nil

Produces the lexical form of an invalid value of a typed Literal.

The default implementation of the _using__ macro just returns to_string representation of the value.

Produces the lexical form of a RDF.Literal.

Determines if the value of a RDF.Literal is a member of lexical value space of its datatype.