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5.4.2.17 Variant

Variant values shall be encoded as a JSON object with the fields shown in Table 35.

Table 35 – 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 a 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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