derive_optic was removed but the README still references it.

https://github.com/TOETOE55/lens-rs/commit/3c19d0d2516dd0ca128972bcd194da861cf0ae5d#diff-dc4a22e0b81ffbabfdb6f61ae197ca2f0a406ddf9141d14e930b56b5df7b3a74R41

How can we have optics on struct fields now?

I know this crate is very new, but I'm excited about it. Nice work!

When I build I see

   Compiling lens-rs v0.3.2 (.../repos/lens-rs/lens-rs)
 error[E0583]: file not found for module `dyn_optics`
   --> lens-rs/src/lib.rs:210:1
    |
210 | pub mod dyn_optics;
    | ^^^^^^^^^^^^^^^^^^^
    |
    = help: to create the module `dyn_optics`, create file "lens-rs/src/dyn_optics.rs" or "lens-rs/src/dyn_optics/mod.rs"

It looks like the recent merge added line 210 above, but not the dyn_optics.rs file. Thanks for this crate!

rust version is rustc 1.57.0 (f1edd0429 2021-11-29) With example as blow

#[derive(Copy, Clone, Debug, Review, Prism)]
enum Either<L, R> {
    #[optic]
    Left(L), // generate optics::Left
    #[optic]
    Right(R), // generate optics::Right
}

#[derive(Copy, Clone, Debug, Lens)]
struct Tuple<A, B>(#[optic] A, #[optic] B); 
// use optics::_0 or optics::_1 to access it

#[derive(Copy, Clone, Debug, Lens)]
struct Foo<A, B> {
    #[optic]
    a: A, // generate optics::a
    #[optic]
    b: B, // generate optics::b
}


#[derive(Clone, Debug, Lens)]
struct Bar {
    #[optic]
    a: String, // generate optics::a, same as above
    #[optic]
    c: i32,    // generate optics::c
}```

get error 

```error[E0412]: cannot find type `Left` in module `lens_rs::optics`
  --> src/domain/mod.rs:15:5
   |
15 |     Left(L), // generate optics::Left
   |     ^^^^ not found in `lens_rs::optics`
   |
help: there is an enum variant `core::fmt::Alignment::Left` and 11 others; try using the variant's enum
   |
12 | #[derive(Copy, Clone, Debug, core::fmt::Alignment, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, core::fmt::rt::v1::Alignment, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, crate::domain::Either, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, futures::future::Either, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~~~
     and 7 other candidates

error[E0412]: cannot find type `Right` in module `lens_rs::optics`
  --> src/domain/mod.rs:17:5
   |
17 |     Right(R), // generate optics::Right
   |     ^^^^^ not found in `lens_rs::optics`
   |
help: there is an enum variant `core::fmt::Alignment::Right` and 11 others; try using the variant's enum
   |
12 | #[derive(Copy, Clone, Debug, core::fmt::Alignment, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, core::fmt::rt::v1::Alignment, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, crate::domain::Either, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, futures::future::Either, Prism)]
   |                              ~~~~~~~~~~~~~~~~~~~~~~~
     and 7 other candidates

error[E0412]: cannot find type `Left` in module `lens_rs::optics`
  --> src/domain/mod.rs:15:5
   |
15 |     Left(L), // generate optics::Left
   |     ^^^^ not found in `lens_rs::optics`
   |
help: there is an enum variant `core::fmt::Alignment::Left` and 11 others; try using the variant's enum
   |
12 | #[derive(Copy, Clone, Debug, Review, core::fmt::Alignment)]
   |                                      ~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, core::fmt::rt::v1::Alignment)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, crate::domain::Either)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, futures::future::Either)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~~~
     and 7 other candidates

error[E0412]: cannot find type `Right` in module `lens_rs::optics`
  --> src/domain/mod.rs:17:5
   |
17 |     Right(R), // generate optics::Right
   |     ^^^^^ not found in `lens_rs::optics`
   |
help: there is an enum variant `core::fmt::Alignment::Right` and 11 others; try using the variant's enum
   |
12 | #[derive(Copy, Clone, Debug, Review, core::fmt::Alignment)]
   |                                      ~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, core::fmt::rt::v1::Alignment)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, crate::domain::Either)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~
12 | #[derive(Copy, Clone, Debug, Review, futures::future::Either)]
   |                                      ~~~~~~~~~~~~~~~~~~~~~~~
     and 7 other candidates

error[E0412]: cannot find type `a` in module `lens_rs::optics`
  --> src/domain/mod.rs:27:5
   |
27 |     a: A, // generate optics::a
   |     ^ not found in `lens_rs::optics`

error[E0412]: cannot find type `b` in module `lens_rs::optics`
  --> src/domain/mod.rs:29:5
   |
29 |     b: B, // generate optics::b
   |     ^ not found in `lens_rs::optics`

error[E0412]: cannot find type `a` in module `lens_rs::optics`
  --> src/domain/mod.rs:36:5
   |
36 |     a: String, // generate optics::a, same as above
   |     ^ not found in `lens_rs::optics`

error[E0412]: cannot find type `c` in module `lens_rs::optics`
  --> src/domain/mod.rs:38:5
   |
38 |     c: i32,    // generate optics::c
   |     ^ not found in `lens_rs::optics`

warning: unused import: `ChildStdin`
 --> src/domain/command.rs:3:34
  |
3 | use std::process::{Stdio,Command,ChildStdin};
  |                                  ^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: unused import: `super::validate::validate_raw`
 --> src/domain/model.rs:9:5
  |
9 | use super::validate::validate_raw;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0207]: the type parameter `__Rv` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:12:30
   |
12 | #[derive(Copy, Clone, Debug, Review, Prism)]
   |                              ^^^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Review` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Tr` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:12:38
   |
12 | #[derive(Copy, Clone, Debug, Review, Prism)]
   |                                      ^^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Prism` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Pm` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:12:38
   |
12 | #[derive(Copy, Clone, Debug, Review, Prism)]
   |                                      ^^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Prism` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Tr` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:24:30
   |
24 | #[derive(Copy, Clone, Debug, Lens)]
   |                              ^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Lens` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Pm` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:24:30
   |
24 | #[derive(Copy, Clone, Debug, Lens)]
   |                              ^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Lens` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Ls` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:24:30
   |
24 | #[derive(Copy, Clone, Debug, Lens)]
   |                              ^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Lens` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Tr` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:33:24
   |
33 | #[derive(Clone, Debug, Lens)]
   |                        ^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Lens` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Pm` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:33:24
   |
33 | #[derive(Clone, Debug, Lens)]
   |                        ^^^^ unconstrained type parameter
   |
   = note: this error originates in the derive macro `Lens` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0207]: the type parameter `__Ls` is not constrained by the impl trait, self type, or predicates
  --> src/domain/mod.rs:33:24
   |
33 | #[derive(Clone, Debug, Lens)]
   |                        ^^^^ unconstrained type parameter

Can you please give a example project can pass build.

I get the following test errors when i try to do cargo test:

failures: src/lib.rs - (line 103) src/lib.rs - (line 115) src/lib.rs - (line 131) src/lib.rs - (line 182) src/lib.rs - (line 222) src/lib.rs - (line 35) src/lib.rs - (line 45) src/lib.rs - (line 54) src/lib.rs - (line 63) src/lib.rs - (line 72) src/lib.rs - (line 87) src/lib.rs - Optics (line 222) src/lib.rs - optics (line 222) src/traits.rs - traits::prism (line 56) src/traits.rs - traits::traversal (line 24)

1. Specify path for the dependency of lens-rs_derive in lens-rs's Cargo.toml.
  According to the [cargo book](https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html?highlight=specify%20depend#multiple-locations):
  > One example where this can be useful is when you have split up a library into multiple packages within the same workspace. You can then use path dependencies to point to the local packages within the workspace to use the local version during development, and then use the crates.io version once it is published.

2. Crate lens-rs_derive adds experimental support for deriving lens_rs::{Optic, Review, Prism, Lens} for [structx](https://github.com/oooutlk/structx/tree/structx_derives_lens).