Basics

The fieldx module provides two attributes: fxstruct, which is the actual macro and configures named structs (no unions or enums are supported), and fieldx, which adjusts field parameters.

When applied, the fxstruct macro transforms the annotated struct based on its own arguments and any subsidiary fieldx attributes. Notable changes and additions may include, but are not limited to:

• Wrapping field types in container types (see The Inner Workings). In the introduction example, comment and count become OnceCell<String> and OnceCell<usize>, while order remains unchanged.

• Generating helper methods and associated functions for the struct. This includes accessor methods and the new() associated method.

• Implementing the Default trait.

• Generating a builder type and the builder() associated method.

• Generating a shadow struct for serialization/deserialization with serde.

The following chapters will introduce you into FieldX, covering basics of these and other topics.