#field-name #proc-macro #macro #query #database #struct-fields #generate

macro runtime-struct-field-names-as-array

Provides a procedural macro that generates an array of the field names of a named struct

1 unstable release

0.1.0 Mar 21, 2023

#868 in Procedural macros

Download history 20927/week @ 2024-11-17 15168/week @ 2024-11-24 22432/week @ 2024-12-01 21044/week @ 2024-12-08 21598/week @ 2024-12-15 2765/week @ 2024-12-22 6308/week @ 2024-12-29 19938/week @ 2025-01-05 26341/week @ 2025-01-12 19343/week @ 2025-01-19 22649/week @ 2025-01-26 20489/week @ 2025-02-02 25319/week @ 2025-02-09 20383/week @ 2025-02-16 27292/week @ 2025-02-23 29330/week @ 2025-03-02

103,121 downloads per month

MIT license

8KB
85 lines

runtime-struct-field-names-as-array

crate-name at crates.io crate-name at docs.rs Rust

Provides the FieldNamesAsArray procedural macro. The macro adds the fn field_names_as_array() to the struct the macro is derived on. It contains the field names of the given struct, including the parents

Note: The macro can only be derived from named structs.

IMPORTANT This crate has a runtime overhead while it has limited options. If you do NOT intend to use it on a nested struct, you shall use this crate instead. See discussion

Table of Contents

Usage

You can derive the FieldNamesAsArray macro like this:

use runtime_struct_field_names_as_array::FieldNamesAsArray;

#[derive(FieldNamesAsArray)]
struct Foo {
  bar: String,
  baz: String,
  bat: String,
}

assert_eq!(Foo::field_names_as_array(), ["bar", "baz", "bat"]);

Attributes

The FieldNamesAsArray macro supports the field_names_as_array attribute. field_names_as_array can be applied to a field with only the flatten attribute

Container Attributes

Container attributes are global attributes that change the behavior of the whole field names array, rather than that of a single field.

Field Attributes

Field attributes can be added to the fields of a named struct and change the behavior of a single field.

Flatten

The flatten attribute will add the parent fields. Option struct are also supported. If the attribute is not added on a struct type, it will be considered as a regular field.

use runtime_struct_field_names_as_array::FieldNamesAsArray;

#[derive(FieldNamesAsArray)]
struct Parent {
  foo: String,
}

#[derive(FieldNamesAsArray)]
struct Foo {
  bar: String,
  baz: String,
  #[field_names_as_array(flatten)]
  parent: Parent,
  #[field_names_as_array(flatten)]
  parent_option: Option<Parent>,
  another_parent: Parent,
}

assert_eq!(Foo::field_names_as_array(), ["bar", "baz", "parent.foo", "parent_option.foo", "another_parent"]);

Dependencies

~215–660KB
~16K SLoC