1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
//! jlrs is a crate that provides access to most of the Julia C API, it can be used to embed Julia
//! in Rust applications and to use functionality from the Julia C API when writing `ccall`able
//! functions in Rust. Currently this crate is only tested on Linux and Windows in combination
//! with Julia 1.6 and 1.8 and is not compatible with other versions of Julia.
//!
//! The documentation assumes you're already familiar with the Julia programming language.
//!
//! An incomplete list of features that are currently supported by jlrs:
//!
//!  - Access arbitrary Julia modules and their contents.
//!  - Call Julia functions, including functions that take keyword arguments.
//!  - Handle exceptions or convert them to an error message, optionally with color.
//!  - Include and call your own Julia code.
//!  - Use a custom system image.
//!  - Create values that Julia can use, and convert them back to Rust, from Rust.
//!  - Access the type information and fields of values. The contents of inline and bits-union
//!    fields can be accessed directly.
//!  - Create and use n-dimensional arrays. The `jlrs-ndarray` feature can be enabled for
//!    integration with ndarray.
//!  - Support for mapping Julia structs to Rust structs that can be generated by JlrsReflect.jl.
//!  - Structs that can be mapped to Rust include those with type parameters and bits unions.
//!  - An async runtime is available which can be used from multiple threads and supports
//!    scheduling Julia `Task`s and `await`ing the result without blocking the runtime thread.
//!
//! NB: Active development happens on the `dev` branch, the `master` branch points to the most
//! recently released version.
//!
//! # Prerequisites
//!
//! Julia must be installed before jlrs can be used. Only version  1.6 and 1.8 are
//! supported. Using version 1.6 requires enabling the `lts` feature.
//!
//! ## Linux
//!
//! The recommended way to install Julia is to download the binaries from the official website,
//! which is distributed in an archive containing a directory called `julia-x.y.z`. This directory
//! contains several other directories, including a `bin` directory containing the `julia`
//! executable.
//!
//! During compilation, the paths to the header and library are normally detected automatically by
//! executing the command `which julia`. The path to `julia.h` must be
//! `$(which julia)/../include/julia/julia.h` and the path to the library
//! `$(which julia)/../lib/libjulia.so`. If you want to override this default behaviour the
//! `JULIA_DIR` environment variable must be set to the path to the appropriate `julia.x-y-z`
//! directory; in this case `$JULIA_DIR/include/julia/julia.h` and
//! `$JULIA_DIR/lib/libjulia.so` are used instead.
//!
//! In order to be able to load `libjulia.so` this file must be on the library search path. If
//! this is not the case you must add `/path/to/julia-x.y.z/lib` to the `LD_LIBRARY_PATH`
//! environment variable. When the `uv` feature is enabled, `/path/to/julia-x.y.z/lib/julia` must
//! also be added to `LD_LIBRARY_PATH`. The latter path should not be added to the default path
//! because this can break tools currently installed on your system.
//!
//! ## Windows
//!
//! Julia can be installed using juliaup, or with the installer or portable installation
//! downloaded from the official website. In the first case, Julia has been likely placed in
//! `%USERPROFILE%\.julia\juliaup\julia-x.y.z+0~x64`, while installing or extracting allows
//! you to pick the destination. After installation or extraction a folder called `Julia-x.y.z`
//! exists, which contains several folders including a `bin` folder containing `julia.exe`. The
//! path to the `bin` folder must be added to the `Path` environment variable.
//!
//! Julia is automatically detected by executing the command `where julia`. If this returns
//! multiple locations the first one is used. The default can be overridden by setting the
//! `JULIA_DIR` environment variable. This doesn't work correctly with juliaup, in this case
//! the environment variable must be set.
//!
//! Note that while Julia 1.6 is supported on Windows, several methods are currently unavailable
//! when this version is used.
//!
//! If you use the MSVC target, you must create two or three lib files using `lib.exe`. The def
//! files required for this can be found in the [`def` folder] in the jl-sys crate. To create the
//! lib files, copy the three files from either the `lts` or `stable` folder to the `bin`
//! folder where Julia is installed. Afterwards, open a Developer Command Prompt for VS19 and
//! execute the following commands:
//!
//! ```cmd
//! cd C:\Path\To\Julia-x.y.z\bin
//! lib /def:libjulia.def /out:libjulia.lib /machine:x64
//! lib /def:libopenlibm.def /out:libopenlibm.lib /machine:x64
//! lib /def:libuv-2.def /out:libuv-2.lib /machine:x64
//! ```
//!
//! The final command only needs to be executed if the `uv` feature has been enabled. If you use
//! the GNU target these lib files must not exist.
//!
//! # Features
//!
//! Most functionality of jlrs is only available if the proper features are enabled. These
//! features generally belong to one of two categories: runtimes and utilities.
//!
//! A runtime lets you call Julia from Rust, you must enable one of them if you want to embed
//! Julia in a Rust application. The following features enable a runtime:
//!
//! - `sync-rt`
//!   Enables the sync runtime, [`Julia`]. The sync runtime provides single-threaded, blocking
//!   access to the Julia C API.
//!
//! - `async-rt`
//!   Enables the async runtime, [`AsyncJulia`]. The async runtime runs on a separate thread and
//!   can be used from multiple threads. While access to the C API is single-threaded, the async
//!   runtime can run multiple tasks in parallel by making use of Julia's task system and Rust's
//!   async/await syntax. To use this feature you must provide a backing runtime.
//!
//! - `tokio-rt` and `async-std-rt`
//!   These features provide a backing runtime for the async runtime. The first uses tokio, the
//!   second async-std. The `async-rt` feature is automatically enabled when one of these features
//!   is enabled.
//!
//! If you're writing a library, either one that will be called from Julia or one that will be
//! used by a Rust application that embeds Julia, no runtime is required.
//!
//! In addition to these runtimes, the following utility features are available:
//!
//! - `prelude`
//!   Provide a prelude module, [`jlrs::prelude`]. This feature is enabled by default.
//!
//! - `lts`
//!
//!   Use the current LTS version of Julia (1.6) instead of the current stable version (1.8).
//!
//! - `async`
//!
//!   Enable the features of the async runtime which don't depend on the backing runtime. This
//!   can be used in libraries which provide implementations of tasks that the async runtime can
//!   handle.
//!
//! - `jlrs-derive`
//!
//!   This features should be used in combination with the JlrsReflect.jl package. This package
//!   generates Rust bindings for Julia structs, these bindings use the custom derive macros to
//!   enable the safe conversion of data from Julia to Rust, and from Rust to Julia in some cases.
//!
//! - `jlrs-ndarray`
//!
//!   Access the contents of a Julia array as an `ArrayView` or `ArrayViewMut` from ndarray.
//!
//! - `f16`
//!
//!   Adds support for working with Julia's `Float16` type from Rust using half's `f16` type.
//!
//! - `ccall`
//!
//!   Julia's `ccall` interface can be used to call functions written in Rust from Julia. No
//!   runtime can be used in this case because Julia has already been initialized, when this
//!   feature is enabled the `CCall` struct is available which offers the same functionality as
//!   the sync runtime without initializing Julia.
//!
//! - `uv`
//!
//!   This feature enables the method `CCall::uv_async_send`, which can be used to wake a Julia
//!   `AsyncCondition` from Rust. The `ccall` feature is automically enabled when this feature
//!   is used.
//!
//! - `pyplot`
//!
//!   This feature lets you plot data using the Pyplot package and Gtk 3 from Rust.
//!
//! - `i686`
//!
//!   Link with a 32-bit build of Julia.
//!
//! - `debug`
//!
//!   Link with a debug build of Julia on Linux.
//!
//! You can enable all features except `lts` and `debug` by enabling the `full` feature.
//!
//!
//! # Using this crate
//!
//! If you want to embed Julia and call it from Rust, you must enable a runtime feature:
//!
//! `jlrs = {version = "0.16", features = ["sync-rt"]}`
//!
//! `jlrs = {version = "0.16", features = ["tokio-rt"]}`
//!
//! `jlrs = {version = "0.16", features = ["async-std-rt"]}`
//!
//! When Julia is embedded in an application, it must be initialized before it can be used. The
//! following snippet initializes the sync runtime:
//!
//! ```no_run
//! use jlrs::prelude::*;
//!
//! # fn main() {
//! // Initializing Julia is unsafe because this can load arbitrary
//! // Julia code, and because it can race with other crates unrelated
//! // to jlrs. It returns an error if Julia has already been
//! // initialized.
//! let _julia = unsafe { RuntimeBuilder::new().start().unwrap() };
//! # }
//! ```
//!
//! To use the async runtime you must upgrade the [`RuntimeBuilder`] to an
//! [`AsyncRuntimeBuilder`] by providing a backing runtime and channel. Implementations for tokio
//! and async-std are available if these features have been enabled. For example, an async runtime
//! backed by tokio and an unbounded channel can be initialized as follows if the `tokio-rt`
//! feature is enabled:
//!
//! ```no_run
//! use jlrs::prelude::*;
//!
//! # fn main() {
//! // Initializing Julia is unsafe for the same reasons as the sync runtime.
//! let (_julia, _task_handle) = unsafe {
//!     RuntimeBuilder::new()
//!         .async_runtime::<Tokio, UnboundedChannel<_>>()
//!         .start()
//!         .unwrap()
//! };
//! # }
//! ```
//!
//! The async runtime can also be started asynchronously:
//!
//! ```no_run
//! use jlrs::prelude::*;
//!
//! #[tokio::main]
//! async fn main() {
//!     // Initializing Julia is unsafe for the same reasons as the sync runtime.
//!     let (_julia, _task_handle) = unsafe {
//!         RuntimeBuilder::new()
//!             .async_runtime::<Tokio, UnboundedChannel<_>>()
//!             .start_async()
//!             .unwrap()
//!     };
//! }
//! ```
//!
//! If you're calling Rust from Julia everything has already been initialized. If the `ccall`
//! feature is enabled [`CCall`] is available which provides the same functionality as the sync
//! runtime.
//!
//! ## Calling Julia from Rust
//!
//! This section will focus on some topics that are common between the sync and async runtimes.
//!
//! After initialization you have an instance of [`Julia`] or [`AsyncJulia`], both provide a
//! method called `include` that lets you include files with custom Julia code. In order to
//! create Julia data and call Julia functions, a scope must be created.
//!
//! When the sync runtime is used this can be done by calling the methods [`Julia::scope`] and
//! [`Julia::scope_with_capacity`]. These methods take a closure with two arguments, a [`Global`]
//! and a [`GcFrame`] (frame). The first is an access token for global Julia data, the second is
//! used to root non-global data. While non-global data is rooted, it won't be freed by Julia's
//! garbage collector. The frame is created when `Julia::scope(_with_capacity)` is called and
//! dropped when it returns, so any data rooted in the frame associated with a scope won't be
//! freed by the garbage collector until leaving that scope.
//!
//! The async runtime can't create a new scope directly, `AsyncJulia` is a handle to the async
//! runtime which runs on another thread. Instead, the async runtime deals with tasks. The
//! simplest of these is a blocking task, which can be executed by calling
//! `AsyncJulia::(try_)blocking_task(_with_capacity)`. These methods accept any closure
//! `Julia::scope` can handle with the additional requirement that it must be `Send` and `Sync`.
//! It's called a blocking task because the runtime is blocked while executing this task. The
//! other kinds of tasks that the async runtime can handle will be introduced later.
//!
//! Inside the closure provided to `Julia::scope` or `AsyncJulia::blocking_task` it's possible to
//! interact with Julia. Global Julia data can be accessed through its module system, the methods
//! [`Module::main`], [`Module::base`], and [`Module::core`] can be used to access the `Main`,
//! `Base`, and `Core` modules respectively. The contents of these modules can then be accessed by
//! calling [`Module::function`] which returns a [`Function`], [`Module::global`] which returns a
//! [`Value`], and [`Module::submodule`] which returns another `Module`.
//!
//! `Value` provides several methods to allocate new Julia data. The simplest one is
//! [`Value::eval_string`], which evaluates the contents of the string passed to it and returns
//! the result as a `Value`. For example, you can evaluate `2` to convert it to  [`Value`]. In
//! practice, this method should rarely be used. It can be used to evaluate simple function calls
//! like `sqrt(2)`, but it must be parsed, compiled, and can't take any arguments. Its most
//! important use-case is importing installed and standard library packages by evaluating an
//! `import` or `using` statement.
//!
//! A more interesting method, [`Value::new`], can be used with data of any type that implements
//! [`IntoJulia`]. This trait is implemented by primitive types like `i8` and `char`. Any type
//! that implements [`IntoJulia`] also implements [`Unbox`] which is used to extract the contents
//! of a `Value`. Because `sqrt(2)` returns a `Float64`, it can be unboxed as an `f64`. Pointer
//! wrapper types don't implement [`IntoJulia`] or [`Unbox`], if they can be created from Rust
//! they provide methods to do so.
//!
//! It's possible to call anything that implements [`Call`] as a Julia function. Functions can be
//! called with any number of positional arguments and can be provided with keyword arguments.
//! Keywords must be provided as a `NamedTuple`, which can be created with the [`named_tuple`]
//! macro.
//!
//! Evaluating raw code and calling Julia functions is always unsafe. Nothing prevents you from
//! calling a function like `nasaldemons() = unsafe_load(Ptr{Float64}(0x05391A445))`. Similarly,
//! mutating Julia data is unsafe because nothing prevents you from mutating data that shouldn't
//! be mutated, e.g. the contents of the `Core` module. A full overview of the rules that you
//! should keep in mind can be found in the [`safety`] module.
//!
//! As a simple example, let's convert two numbers to Julia values and add them:
//!
//! ```no_run
//! use jlrs::prelude::*;
//!
//! # fn main() {
//! // Initializing Julia is unsafe because it can race with another crate that does
//! // the same.
//! let mut julia = unsafe { RuntimeBuilder::new().start().unwrap() };
//!
//! let res = julia.scope(|global, mut frame| {
//!     // Create the two arguments.
//!     let i = Value::new(&mut frame, 2u64)?;
//!     let j = Value::new(&mut frame, 1u32)?;
//!
//!     // The `+` function can be found in the base module.
//!     let func = Module::base(global).function(&mut frame, "+")?;
//!
//!     // Call the function and unbox the result as a `u64`. The result of the function
//!     // call is a nested `Result`; the outer error doesn't contain to any Julia
//!     // data, while the inner error contains the exception if one is thrown. Here the
//!     // exception is converted to the outer error type by calling `into_jlrs_result`, this new
//!     // error contains the error message Julia would have shown.
//!     unsafe { func.call2(&mut frame, i, j)? }
//!         .into_jlrs_result()?
//!         .unbox::<u64>()
//! }).unwrap();
//!
//! assert_eq!(res, 3);
//! # }
//! ```
//!
//! ### Async and persistent tasks
//!
//! In addition to blocking tasks, the async runtime lets you execute async tasks which implement
//! the [`AsyncTask`] trait, and persistent tasks which implement [`PersistentTask`]. Both of
//! these traits are async traits.
//!
//! An async task is similar to a blocking task, except that you must implement the async `run`
//! method instead of providing a closure. This method takes a `Global` and a an [`AsyncGcFrame`].
//! This new frame type not only provides access to the same features as [`GcFrame`], it can also
//! be used to call async methods provided by the [`CallAsync`] trait. These methods schedule a
//! function call as a new Julia `Task` and can be `await`ed until this task has completed. The
//! async runtime can switch to another task while the result is pending, allowing multiple tasks
//! to progress.
//!
//! The previous example can be rewritten as an async task:
//!
//! ```
//! use jlrs::prelude::*;
//!
//! struct AdditionTask {
//!     a: u64,
//!     b: u32,
//! }
//!
//! // Only the runtime thread can call the Julia C API, so the async
//! // trait methods of `AsyncTask` must not return a future that
//! // implements `Send` or `Sync`.
//! #[async_trait(?Send)]
//! impl AsyncTask for AdditionTask {
//!     // The type of the result of this task if it succeeds.
//!     type Output = u64;
//!
//!     // This async method replaces the closure from the previous examples,
//!     // an `AsyncGcFrame` can be used the same way as a `GcFrame` but also
//!     // can be used in combination with methods from the `CallAsync` trait.
//!     async fn run<'frame>(
//!         &mut self,
//!         global: Global<'frame>,
//!         mut frame: AsyncGcFrame<'frame>,
//!     ) -> JlrsResult<Self::Output> {
//!         let a = Value::new(&mut frame, self.a)?;
//!         let b = Value::new(&mut frame, self.b)?;
//!             
//!         let func = Module::base(global).function(&mut frame, "+")?;
//!
//!         // CallAsync::call_async schedules the function call on another
//!         // thread and returns a Future that resolves when the scheduled
//!         // function has returned or thrown an error.
//!         unsafe { func.call_async(&mut frame, &mut [a, b]) }
//!             .await?
//!             .into_jlrs_result()?
//!             .unbox::<u64>()
//!     }
//! }
//! ```
//!
//! While blocking and async tasks run once and return their result, a persistent task returns a
//! handle. This handle can be shared across threads and used to call its `run` method. In
//! addition to a global and an async frame, this method can use the state and input data provided
//! by the caller.
//!
//! As an example, let's accumulate some number of values in a Julia array and return the sum of
//! its contents:
//!
//! ```
//! # #[cfg(not(all(target_os = "windows", feature = "lts")))]
//! # {
//! use jlrs::prelude::*;
//!
//! struct AccumulatorTask {
//!     n_values: usize
//! }
//!
//! struct AccumulatorTaskState {
//!     array: TypedArray<'static, 'static, usize>,
//!     offset: usize
//! }
//!
//! // Only the runtime thread can call the Julia C API, so the async trait
//! // methods of `PersistentTask` must not return a future that implements
//! // `Send` or `Sync`.
//! #[async_trait(?Send)]
//! impl PersistentTask for AccumulatorTask {
//!     // The type of the result of the task if it succeeds.
//!     type Output = usize;
//!     // The type of the task's internal state.
//!     type State = AccumulatorTaskState;
//!     // The type of the additional data that the task must be called with.
//!     type Input = usize;
//!
//!     // This method is called before the task can be called. Note that the
//!     // lifetime of the frame is `'static`: the frame is not dropped until
//!     // the task has completed, so the task's internal state can contain
//!     // Julia data rooted in this frame.
//!     async fn init(
//!         &mut self,
//!         _global: Global<'static>,
//!         frame: &mut AsyncGcFrame<'static>,
//!     ) -> JlrsResult<Self::State> {
//!         // A `Vec` can be moved from Rust to Julia if the element type
//!         // implements `IntoJulia`.
//!         let data = vec![0usize; self.n_values];
//!         let array = TypedArray::from_vec(&mut *frame, data, self.n_values)?
//!             .into_jlrs_result()?;
//!     
//!         Ok(AccumulatorTaskState {
//!             array,
//!             offset: 0
//!         })
//!     }
//!     
//!     // Whenever the task is called through its handle this method
//!     // is called. Unlike `init`, the frame that this method can use
//!     // is dropped after `run` returns.
//!     async fn run<'frame>(
//!         &mut self,
//!         global: Global<'static>,
//!         mut frame: AsyncGcFrame<'frame>,
//!         state: &mut Self::State,
//!         input: Self::Input,
//!     ) -> JlrsResult<Self::Output> {
//!         {
//!             // Array data can be directly accessed from Rust.
//!             // TypedArray::bits_data_mut can be used if the type
//!             // of the elements is concrete and immutable.
//!             // This is safe because this is the only active reference to
//!             // the array.
//!             let mut data = unsafe { state.array.bits_data_mut(&mut frame)? };
//!             data[state.offset] = input;
//!
//!             state.offset += 1;
//!             if (state.offset == self.n_values) {
//!                 state.offset = 0;
//!             }
//!         }
//!
//!         // Return the sum of the contents of `state.array`.
//!         unsafe {
//!             Module::base(global)
//!                 .function(&mut frame, "sum")?
//!                 .call1(&mut frame, state.array.as_value())?
//!                 .into_jlrs_result()?
//!                 .unbox::<usize>()
//!         }
//!     }
//! }
//! # }
//! ```
//!
//! ## Calling Rust from Julia
//!
//! Julia's `ccall` interface can be used to call `extern "C"` functions defined in Rust, for most
//! use-cases you shouldn't need jlrs. There are two major ways to use `ccall`, with a pointer to
//! the function or a `(:function, "library")` pair.
//!
//! A function can be cast to a void pointer and converted to a [`Value`]:
//!
//! ```no_run
//! use jlrs::prelude::*;
//!
//! // This function will be provided to Julia as a pointer, so its name can be mangled.
//! unsafe extern "C" fn call_me(arg: bool) -> isize {
//!     if arg {
//!         1
//!     } else {
//!         -1
//!     }
//! }
//!
//! # fn main() {
//! let mut julia = unsafe { RuntimeBuilder::new().start().unwrap() };
//! julia.scope(|global, mut frame| unsafe {
//!     // Cast the function to a void pointer
//!     let call_me_val = Value::new(&mut frame, call_me as *mut std::ffi::c_void)?;
//!
//!     // Value::eval_string can be used to create new functions.
//!     let func = Value::eval_string(
//!         &mut frame,
//!         "myfunc(callme::Ptr{Cvoid})::Int = ccall(callme, Int, (Bool,), true)"
//!     )?.into_jlrs_result()?;
//!
//!     // Call the function and unbox the result.
//!     let output = func.call1(&mut frame, call_me_val)?
//!         .into_jlrs_result()?
//!         .unbox::<isize>()?;
//!
//!     assert_eq!(output, 1);
//!
//!     Ok(())
//! }).unwrap();
//! # }
//! ```
//!
//! You can also use functions defined in `dylib` and `cdylib` libraries. In order to create such
//! a library you need to add
//!
//! ```toml
//! [lib]
//! crate-type = ["dylib"]
//! ```
//!
//! or
//!
//! ```toml
//! [lib]
//! crate-type = ["cdylib"]
//! ```
//!
//! respectively to your crate's `Cargo.toml`. Use a `dylib` if you want to use the crate in other
//! Rust crates, but if it's only intended to be called through `ccall` a `cdylib` is the better
//! choice. On Linux, such a crate will be compiled to `lib<crate_name>.so`.
//!
//! The functions you want to use with `ccall` must be both `extern "C"` functions to ensure the C
//! ABI is used, and annotated with `#[no_mangle]` to prevent name mangling. Julia can find
//! libraries in directories that are either on the default library search path or included by
//! setting the `LD_LIBRARY_PATH` environment variable on Linux. If the compiled library is not
//! directly visible to Julia, you can open it with `Libdl.dlopen` and acquire function pointers
//! with `Libdl.dlsym`. These pointers can be called the same way as the pointer in the previous
//! example.
//!
//! If the library is visible to Julia you can access it using the library name. If `call_me` is
//! defined in a crate called `foo`, the following should work:
//!
//! ```julia
//! ccall((:call_me, "libfoo"), Int, (Bool,), false)
//! ```
//!
//! One important aspect of calling Rust from other languages in general is that panicking across
//! an FFI boundary is undefined behaviour. If you're not sure your code will never panic, wrap it
//! with `std::panic::catch_unwind`.
//!
//! Most features provided by jlrs including accessing modules, calling functions, and borrowing
//! array data require a [`Global`] or a frame. You can access these by creating an instance of
//! [`CCall`] first. Another method provided by [`CCall`] is [`CCall::uv_async_send`], this method
//! can be used to wake an `Base.AsyncCondition`. In particular, it can be used to write a
//! `ccall`able function that does its actual work on another thread, returns early and then
//! `wait`ing on the async condition from Julia. The advantage of this is that the long-running
//! function won't block Julia. In this case you will need to use `GC.@preserve` to ensure Julia
//! is aware that the use of this data is still in use after the `ccall` has returned.
//!
//!
//! # Testing
//!
//! The restriction that Julia can be initialized once must be taken into account when running
//! tests that use `jlrs`. The recommended approach is to create a thread-local static `RefCell`:
//!
//! ```no_run
//! use jlrs::prelude::*;
//! use std::cell::RefCell;
//! thread_local! {
//!     pub static JULIA: RefCell<Julia> = {
//!         let julia = RefCell::new(unsafe { RuntimeBuilder::new().start().unwrap() });
//!
//!         /* include everything you need to use */
//!
//!         julia
//!     };
//! }
//! ```
//!
//! A similar approach works for the async runtime:
//!
//! ```no_run
//! use jlrs::prelude::*;
//! use std::cell::RefCell;
//! thread_local! {
//!     pub static JULIA: RefCell<AsyncJulia<Tokio>> = {
//!         let julia = RefCell::new(unsafe {
//!             RuntimeBuilder::new()
//!                 .async_runtime::<Tokio, UnboundedChannel<_>>()
//!                 .start()
//!                 .unwrap()
//!                 .0
//!         });
//!
//!         /* include everything you need to use */
//!
//!         julia
//!     };
//! }
//! ```
//!
//! Tests that use these constructs can only use one thread for testing, so you must use
//! `cargo test -- --test-threads=1`, otherwise the code above will panic when a test tries to
//! initialize Julia a second time from another thread.
//!
//! If you want to run all of jlrs's tests, this requirement must be taken into account:
//! `cargo test --all-features -- --test-threads=1`. Testing with the `--all-features` flag only
//! works with Julia 1.8 because this overrides the `lts` and `debug` features.
//!
//!
//! # Custom types
//!
//! In order to map a struct in Rust to one in Julia you can derive [`ValidLayout`], [`Unbox`],
//! and [`Typecheck`]. If the struct in Julia has no type parameters and is a bits type you can
//! also derive [`IntoJulia`].
//!
//! You normally shouldn't need to implement these structs or traits manually. The JlrsReflect
//! package can generate correct Rust struct and automatically derive the supported traits for
//! types that have no atomic fields, nor any tuple or union fields with type parameters. The
//! reason for this restriction is that the layout of such fields can be very different in a way
//! that can't be easily represented.
//!
//! These custom types can also be used when you call Rust from Julia with `ccall`.
//!
//! [their User Guide]: https://rust-lang.github.io/rust-bindgen/requirements.html
//! [on Microsoft's website]: https://docs.microsoft.com/en-us/windows/wsl/install-win10
//! [the examples directory of the repo]: https://github.com/Taaitaaiger/jlrs/tree/master/examples
//! [`def` folder]: https://github.com/Taaitaaiger/jlrs/tree/master/jl_sys/def
//! [`Julia`]: crate::runtime::sync_rt::Julia
//! [`Julia::scope`]: crate::runtime::sync_rt::Julia::scope
//! [`Julia::scope_with_capacity`]: crate::runtime::sync_rt::Julia::scope_with_capacity
//! [`Julia::init`]: crate::runtime::sync_rt::Julia::init
//! [`AsyncJulia::init`]: crate::multitask::runtime::AsyncJulia::init
//! [`AsyncJulia::init_async`]: crate::multitask::runtime::AsyncJulia::init_async
//! [`Julia::init_with_image`]: crate::runtime::sync_rt::Julia::init_with_image
//! [`CCall`]: crate::ccall::CCall
//! [`CCall::uv_async_send`]: crate::ccall::CCall::uv_async_send
//! [`Global`]: crate::memory::global::Global
//! [`GcFrame`]: crate::memory::frame::GcFrame
//! [`Module`]: crate::wrappers::ptr::module::Module
//! [`Function`]: crate::wrappers::ptr::function::Function
//! [`Value`]: crate::wrappers::ptr::value::Value
//! [`Call`]: crate::call::Call
//! [`Value::eval_string`]: crate::wrappers::ptr::value::Value::eval_string
//! [`Value::new`]: crate::wrappers::ptr::value::Value::new
//! [`Array`]: crate::wrappers::ptr::array::Array
//! [`JuliaString`]: crate::wrappers::ptr::string::JuliaString
//! [`Module::main`]: crate::wrappers::ptr::module::Module::main
//! [`Module::base`]: crate::wrappers::ptr::module::Module::base
//! [`Module::core`]: crate::wrappers::ptr::module::Module::core
//! [`Module::function`]: crate::wrappers::ptr::module::Module::function
//! [`Module::global`]: crate::wrappers::ptr::module::Module::global
//! [`Module::submodule`]: crate::wrappers::ptr::module::Module::submodule
//! [`AsyncJulia::init_with_image`]: crate::multitask::runtime::AsyncJulia::init_with_image
//! [`AsyncJulia::init_with_image_async`]: crate::multitask::runtime::AsyncJulia::init_with_image_async
//! [`IntoJulia`]: crate::convert::into_julia::IntoJulia
//! [`Typecheck`]: crate::layout::typecheck::Typecheck
//! [`ValidLayout`]: crate::layout::valid_layout::ValidLayout
//! [`Unbox`]: crate::convert::unbox::Unbox
//! [`CallAsync::call_async`]: crate::multitask::call_async::CallAsync
//! [`AsyncGcFrame`]: crate::memory::frame::AsyncGcFrame
//! [`Frame`]: crate::memory::frame::Frame
//! [`AsyncTask`]: crate::async_util::task::AsyncTask
//! [`PersistentTask`]: crate::async_util::task::PersistentTask
//! [`PersistentHandle`]: crate::runtime::async_rt::PersistentHandle
//! [`AsyncJulia`]: crate::runtime::async_rt::AsyncJulia
//! [`CallAsync`]: crate::call::CallAsync
//! [`DataType`]: crate::wrappers::ptr::datatype::DataType
//! [`TypedArray`]: crate::wrappers::ptr::array::TypedArray
//! [`Output`]: crate::memory::output::Output
//! [`OutputScope`]: crate::memory::output::OutputScope
//! [`Scope`]: crate::memory::scope::Scope
//! [`Scope::value_scope`]: crate::memory::scope::Scope::value_scope
//! [`Scope::result_scope`]: crate::memory::scope::Scope::result_scope
//! [`RuntimeBuilder`]: crate::runtime::builder::RuntimeBuilder
//! [`AsyncRuntimeBuilder`]: crate::runtime::builder::AsyncRuntimeBuilder
//! [`jlrs::prelude`]: crate::prelude
#![forbid(rustdoc::broken_intra_doc_links)]

#[cfg(any(feature = "sync-rt", feature = "async-rt", feature = "pyplot"))]
macro_rules! init_fn {
    ($name:ident, $include:ident, $file:expr) => {
        pub(crate) static $include: &'static str = include_str!($file);
        pub(crate) unsafe fn $name<'frame, F: $crate::memory::frame::Frame<'frame>>(
            frame: &mut F,
        ) -> () {
            match $crate::wrappers::ptr::value::Value::eval_string(frame, $include) {
                Ok(Ok(_)) => (),
                Ok(Err(e)) => {
                    panic!(
                        "{}",
                        $crate::wrappers::ptr::Wrapper::error_string_or(
                            e,
                            $crate::error::CANNOT_DISPLAY_VALUE
                        )
                    )
                }
                Err(_) => panic!("AllocError during initialization of {}", $file),
            }
        }
    };
}

#[cfg(feature = "async")]
pub mod async_util;
pub mod call;
#[cfg(not(all(target_os = "windows", feature = "lts")))]
pub(crate) mod catch;
#[cfg(feature = "ccall")]
pub mod ccall;
pub mod convert;
pub mod error;
pub mod info;
pub mod layout;
pub mod memory;
#[cfg(feature = "prelude")]
pub mod prelude;
pub(crate) mod private;
#[cfg(feature = "pyplot")]
pub mod pyplot;
#[cfg(any(feature = "sync-rt", feature = "async-rt"))]
pub mod runtime;
pub mod safety;
#[doc(hidden)]
#[cfg(feature = "sync-rt")]
pub mod util;
pub mod wrappers;