mail-derive

This crate provides a custom derives for the mail crate.

---

This crate provides a custom derives for the mail crate.

Currently it only contains the InspectEmbeddedResource derive which allows deriving the InspectEmbeddedResource trait from the mail-template (sub-)crate.

Note this crate will be re-exported through the mail facade in the same way as the other mail- crates are.*

InspectEmbeddedResource

Implements InspectEmbeddedResource by forwarding calls to it's methods to all fields.

Belongs to: mail-template

Applicable to: struct, tuple struct, enum, enum with named fields

Attribute Scope: mail (e.g. #[mail(inspect_skip)])

Field Attributes:

• inspect_skip, don't forward calls to the annotated field
• inspect_with = "(no_mut_fn, mut_fn)", specifies two function which are called with a reference to the field (1st param) and the visitor (2nd param) instead of calling inspect_resource(_mut) on the field. Note that the functions in the tuple are interpreted as paths so e.g. ::some_thing::fn1 would be potentially valid.

(Note that field attributes apply to any kind of field wether it's named or unnamed appears in a struct or enum.)

Type Attributes: None

Enum Variant Attributes:

• inspect_skip, skip over all fields in this enum variant

Example

extern crate mail_template;
#[macro_use]
extern crate mail_derive;

use mail_template::{Embedded, InspectEmbeddedResources};


// Just take this as any kind of type.
type SomeRandomType = u32;

// Let's assume this is imported from another crate.
struct TypeNotImplTrait(SomeRandomType);

#[derive(InspectEmbeddedResources)]
enum A {
  VariA,
  VariB(SomeRandomType, #[mail(inspect_skip)] TypeNotImplTrait),
  VariC {
    f1: SomeRandomType,
    #[mail(inspect_with="(inspect, inspect_mut)")]
    f2: TypeNotImplTrait
  }
}

fn inspect(me: &TypeNotImplTrait, visitor: &mut FnMut(&Embedded)) {
  me.0.inspect_resources(visitor)
}
fn inspect_mut(me: &mut TypeNotImplTrait, visitor: &mut FnMut(&mut Embedded)) {
  me.0.inspect_resources_mut(visitor)
}

# fn main() {}