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5.4.2.17 Variant

Variant values shall be encoded as a JSON object with the fields shown in Table 30.

Table 30 – JSON Object Definition for a Variant

Name

Description

Type

The Built-in type for the value contained in the Body (see Table 1) encoded as JSON number.

If type is 0 (NULL) the Variant contains a NULL value and the containing JSON object shall be omitted or replaced by the JSON literal ‘null’ (when an element of a JSON array).

Body

If the value is a scalar it is encoded using the rules for type specified for the Type.

If the value is a one-dimensional array it is encoded as JSON array (see 5.4.5).

Multi-dimensional arrays are encoded as a one dimensional JSON array which is reconstructed using the value of the Dimensions field (see 5.2.2.16).

Dimensions

The dimensions of the array encoded as an JSON array of JSON numbers.

The Dimensions are omitted for scalar and one-dimensional array values.

For the non-reversible form, Variant values shall be encoded as a JSON object containing only the value of the Body field. The Type and Dimensions fields are dropped. Multi-dimensional arrays are encoded as a multi dimensional JSON array as described in 5.4.5.

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