`FieldDiscriminatorNode`

This node represents a byte discrimination strategy where the data is identified by the default value of a struct field at a given offset. Discriminator nodes are used to distinguish between different types of accounts or instructions in a program.

Attributes

Data

Attribute	Type	Description
`kind`	`"fieldDiscriminatorNode"`	The node discriminator.
`field`	`CamelCaseString`	The name of the `StructFieldTypeNode` we should use to identify the data.
`offset`	`number`	The byte at which the field should be located.

Children

This node has no children.

Functions

`fieldDiscriminatorNode(field, offset?)`

Helper function that creates a FieldDiscriminatorNode object from a field name and an optional offset.

const node = fieldDiscriminatorNode('accountState', 64);

Examples

An account distinguished by a u32 field at offset 0

accountNode({
    data: structTypeNode([
        structFieldTypeNode({
            name: 'discriminator',
            type: numberTypeNode('u32'),
            defaultValue: numberValueNode(42),
            defaultValueStrategy: 'omitted',
        }),
        // ...
    ]),
    discriminators: [fieldDiscriminatorNode('discriminator')],
    // ...
});

An instruction disctinguished by an 8-byte argument at offset 0

instructionNode({
    arguments: [
        instructionArgumentNode({
            name: 'discriminator',
            type: fixedSizeTypeNode(bytesTypeNode(), 8),
            defaultValue: bytesValueNode('base16', '0011223344556677'),
            defaultValueStrategy: 'omitted',
        }),
        // ...
    ],
    discriminators: [fieldDiscriminatorNode('discriminator')],
    // ...
});

FieldDiscriminatorNode.md 2.2 KB 文件历史 原始文件

FieldDiscriminatorNode