extendr_api/robj/
mod.rs

1//! R object handling.
2//!
3//! See. [Writing R Extensions](https://cran.r-project.org/doc/manuals/R-exts.html)
4//!
5//! Fundamental principals:
6//!
7//! * Any function that can break the protection mechanism is unsafe.
8//! * Users should be able to do almost everything without using `libR_sys`.
9//! * The interface should be friendly to R users without Rust experience.
10//!
11
12use std::collections::HashMap;
13use std::iter::IntoIterator;
14use std::ops::{Range, RangeInclusive};
15use std::os::raw;
16
17use extendr_ffi::{
18    dataptr, R_IsNA, R_NilValue, R_compute_identical, R_tryEval, Rboolean, Rcomplex, Rf_getAttrib,
19    Rf_setAttrib, Rf_xlength, COMPLEX, INTEGER, LOGICAL, PRINTNAME, RAW, REAL, SEXPTYPE,
20    SEXPTYPE::*, STRING_ELT, STRING_PTR_RO, TYPEOF, XLENGTH,
21};
22
23use crate::scalar::{Rbool, Rfloat, Rint};
24use crate::*;
25pub use into_robj::*;
26pub use iter::*;
27pub use operators::Operators;
28use prelude::{c64, Rcplx};
29pub use rinternals::Rinternals;
30
31mod debug;
32mod into_robj;
33mod operators;
34mod rinternals;
35mod try_from_robj;
36
37#[cfg(test)]
38mod tests;
39
40/// Wrapper for an R S-expression pointer (SEXP).
41///
42/// Create R objects from rust types and iterators:
43///
44/// ```
45/// use extendr_api::prelude::*;
46/// test! {
47///     // Different ways of making integer scalar 1.
48///     let non_na : Option<i32> = Some(1);
49///     let a : Robj = vec![1].into();
50///     let b = r!(1);
51///     let c = r!(vec![1]);
52///     let d = r!(non_na);
53///     let e = r!([1]);
54///     assert_eq!(a, b);
55///     assert_eq!(a, c);
56///     assert_eq!(a, d);
57///     assert_eq!(a, e);
58///
59///     // Different ways of making boolean scalar TRUE.
60///     let a : Robj = true.into();
61///     let b = r!(TRUE);
62///     assert_eq!(a, b);
63///
64///     // Create a named list
65///     let a = list!(a = 1, b = "x");
66///     assert_eq!(a.len(), 2);
67///
68///     // Use an iterator (like 1:10)
69///     let a = r!(1 ..= 10);
70///     assert_eq!(a, r!([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]));
71///
72///     // Use an iterator (like (1:10)[(1:10) %% 3 == 0])
73///     let a = (1 ..= 10).filter(|v| v % 3 == 0).collect_robj();
74///     assert_eq!(a, r!([3, 6, 9]));
75/// }
76/// ```
77///
78/// Convert to/from Rust vectors.
79///
80/// ```
81/// use extendr_api::prelude::*;
82/// test! {
83///     let a : Robj = r!(vec![1., 2., 3., 4.]);
84///     let b : Vec<f64> = a.as_real_vector().unwrap();
85///     assert_eq!(a.len(), 4);
86///     assert_eq!(b, vec![1., 2., 3., 4.]);
87/// }
88/// ```
89///
90/// Iterate over names and values.
91///
92/// ```
93/// use extendr_api::prelude::*;
94/// test! {
95///     let abc = list!(a = 1, b = "x", c = vec![1, 2]);
96///     let names : Vec<_> = abc.names().unwrap().collect();
97///     let names_and_values : Vec<_> = abc.as_list().unwrap().iter().collect();
98///     assert_eq!(names, vec!["a", "b", "c"]);
99///     assert_eq!(names_and_values, vec![("a", r!(1)), ("b", r!("x")), ("c", r!(vec![1, 2]))]);
100/// }
101/// ```
102///
103/// NOTE: as much as possible we wish to make this object safe (ie. no segfaults).
104///
105/// If you avoid using unsafe functions it is more likely that you will avoid
106/// panics and segfaults. We will take great trouble to ensure that this
107/// is true.
108///
109#[repr(transparent)]
110pub struct Robj {
111    inner: SEXP,
112}
113
114impl Clone for Robj {
115    fn clone(&self) -> Self {
116        unsafe { Robj::from_sexp(self.get()) }
117    }
118}
119
120impl Default for Robj {
121    fn default() -> Self {
122        Robj::from(())
123    }
124}
125
126pub trait GetSexp {
127    /// Get a copy of the underlying SEXP.
128    ///
129    /// # Safety
130    ///
131    /// Access to a raw SEXP pointer can cause undefined behaviour and is not thread safe.
132    unsafe fn get(&self) -> SEXP;
133
134    /// # Safety
135    ///
136    /// Access to a raw SEXP pointer can cause undefined behaviour and is not thread safe.
137    unsafe fn get_mut(&mut self) -> SEXP;
138
139    /// Get a reference to a Robj for this type.
140    fn as_robj(&self) -> &Robj;
141
142    /// Get a mutable reference to a Robj for this type.
143    fn as_robj_mut(&mut self) -> &mut Robj;
144}
145
146impl GetSexp for Robj {
147    unsafe fn get(&self) -> SEXP {
148        self.inner
149    }
150
151    unsafe fn get_mut(&mut self) -> SEXP {
152        self.inner
153    }
154
155    fn as_robj(&self) -> &Robj {
156        unsafe { std::mem::transmute(&self.inner) }
157    }
158
159    fn as_robj_mut(&mut self) -> &mut Robj {
160        unsafe { std::mem::transmute(&mut self.inner) }
161    }
162}
163
164pub trait Slices: GetSexp {
165    /// Get an immutable slice to this object's data.
166    ///
167    /// # Safety
168    ///
169    /// Unless the type is correct, this will cause undefined behaviour.
170    /// Creating this slice will also instantiate an Altrep objects.
171    unsafe fn as_typed_slice_raw<T>(&self) -> &[T] {
172        let len = XLENGTH(self.get()) as usize;
173        let data = dataptr(self.get()) as *const T;
174        std::slice::from_raw_parts(data, len)
175    }
176
177    /// Get a mutable slice to this object's data.
178    ///
179    /// # Safety
180    ///
181    /// Unless the type is correct, this will cause undefined behaviour.
182    /// Creating this slice will also instantiate Altrep objects.
183    /// Not all objects (especially not list and strings) support this.
184    unsafe fn as_typed_slice_raw_mut<T>(&mut self) -> &mut [T] {
185        let len = XLENGTH(self.get()) as usize;
186        let data = dataptr(self.get_mut()) as *mut T;
187        std::slice::from_raw_parts_mut(data, len)
188    }
189}
190
191impl Slices for Robj {}
192
193pub trait Length: GetSexp {
194    /// Get the extended length of the object.
195    /// ```
196    /// use extendr_api::prelude::*;
197    /// test! {
198    ///
199    /// let a : Robj = r!(vec![1., 2., 3., 4.]);
200    /// assert_eq!(a.len(), 4);
201    /// }
202    /// ```
203    fn len(&self) -> usize {
204        unsafe { Rf_xlength(self.get()) as usize }
205    }
206
207    /// Returns `true` if the `Robj` contains no elements.
208    /// ```
209    /// use extendr_api::prelude::*;
210    /// test! {
211    ///
212    /// let a : Robj = r!(vec![0.; 0]); // length zero of numeric vector
213    /// assert_eq!(a.is_empty(), true);
214    /// }
215    /// ```
216    fn is_empty(&self) -> bool {
217        self.len() == 0
218    }
219}
220
221impl Length for Robj {}
222
223impl Robj {
224    /// # Safety
225    ///
226    /// This function dereferences a raw SEXP pointer.
227    /// The caller must ensure that `sexp` is a valid SEXP pointer.
228    pub unsafe fn from_sexp(sexp: SEXP) -> Self {
229        single_threaded(|| {
230            unsafe { ownership::protect(sexp) };
231            Robj { inner: sexp }
232        })
233    }
234}
235
236pub trait Types: GetSexp {
237    #[doc(hidden)]
238    /// Get the XXXSXP type of the object.
239    fn sexptype(&self) -> SEXPTYPE {
240        unsafe { TYPEOF(self.get()) }
241    }
242
243    /// Get the type of an R object.
244    /// ```
245    /// use extendr_api::prelude::*;
246    /// test! {
247    ///     assert_eq!(r!(NULL).rtype(), Rtype::Null);
248    ///     assert_eq!(sym!(xyz).rtype(), Rtype::Symbol);
249    ///     assert_eq!(r!(Pairlist::from_pairs(vec![("a", r!(1))])).rtype(), Rtype::Pairlist);
250    ///     assert_eq!(R!("function() {}")?.rtype(), Rtype::Function);
251    ///     assert_eq!(Environment::new_with_parent(global_env()).rtype(), Rtype::Environment);
252    ///     assert_eq!(lang!("+", 1, 2).rtype(), Rtype::Language);
253    ///     assert_eq!(Rstr::from_string("hello").rtype(), Rtype::Rstr);
254    ///     assert_eq!(r!(TRUE).rtype(), Rtype::Logicals);
255    ///     assert_eq!(r!(1).rtype(), Rtype::Integers);
256    ///     assert_eq!(r!(1.0).rtype(), Rtype::Doubles);
257    ///     assert_eq!(r!("1").rtype(), Rtype::Strings);
258    ///     assert_eq!(r!(List::from_values(&[1, 2])).rtype(), Rtype::List);
259    ///     assert_eq!(parse("x + y")?.rtype(), Rtype::Expressions);
260    ///     assert_eq!(r!(Raw::from_bytes(&[1_u8, 2, 3])).rtype(), Rtype::Raw);
261    /// }
262    /// ```
263    fn rtype(&self) -> Rtype {
264        use SEXPTYPE::*;
265        match self.sexptype() {
266            NILSXP => Rtype::Null,
267            SYMSXP => Rtype::Symbol,
268            LISTSXP => Rtype::Pairlist,
269            CLOSXP => Rtype::Function,
270            ENVSXP => Rtype::Environment,
271            PROMSXP => Rtype::Promise,
272            LANGSXP => Rtype::Language,
273            SPECIALSXP => Rtype::Special,
274            BUILTINSXP => Rtype::Builtin,
275            CHARSXP => Rtype::Rstr,
276            LGLSXP => Rtype::Logicals,
277            INTSXP => Rtype::Integers,
278            REALSXP => Rtype::Doubles,
279            CPLXSXP => Rtype::Complexes,
280            STRSXP => Rtype::Strings,
281            DOTSXP => Rtype::Dot,
282            ANYSXP => Rtype::Any,
283            VECSXP => Rtype::List,
284            EXPRSXP => Rtype::Expressions,
285            BCODESXP => Rtype::Bytecode,
286            EXTPTRSXP => Rtype::ExternalPtr,
287            WEAKREFSXP => Rtype::WeakRef,
288            RAWSXP => Rtype::Raw,
289            #[cfg(not(use_objsxp))]
290            S4SXP => Rtype::S4,
291            #[cfg(use_objsxp)]
292            OBJSXP => Rtype::S4,
293            _ => Rtype::Unknown,
294        }
295    }
296
297    fn as_any(&self) -> Rany<'_> {
298        use SEXPTYPE::*;
299        unsafe {
300            match self.sexptype() {
301                NILSXP => Rany::Null(self.as_robj()),
302                SYMSXP => Rany::Symbol(std::mem::transmute::<&Robj, &Symbol>(self.as_robj())),
303                LISTSXP => Rany::Pairlist(std::mem::transmute::<&Robj, &Pairlist>(self.as_robj())),
304                CLOSXP => Rany::Function(std::mem::transmute::<&Robj, &Function>(self.as_robj())),
305                ENVSXP => {
306                    Rany::Environment(std::mem::transmute::<&Robj, &Environment>(self.as_robj()))
307                }
308                PROMSXP => Rany::Promise(std::mem::transmute::<&Robj, &Promise>(self.as_robj())),
309                LANGSXP => Rany::Language(std::mem::transmute::<&Robj, &Language>(self.as_robj())),
310                SPECIALSXP => {
311                    Rany::Special(std::mem::transmute::<&Robj, &Primitive>(self.as_robj()))
312                }
313                BUILTINSXP => {
314                    Rany::Builtin(std::mem::transmute::<&Robj, &Primitive>(self.as_robj()))
315                }
316                CHARSXP => Rany::Rstr(std::mem::transmute::<&Robj, &Rstr>(self.as_robj())),
317                LGLSXP => Rany::Logicals(std::mem::transmute::<&Robj, &Logicals>(self.as_robj())),
318                INTSXP => Rany::Integers(std::mem::transmute::<&Robj, &Integers>(self.as_robj())),
319                REALSXP => Rany::Doubles(std::mem::transmute::<&Robj, &Doubles>(self.as_robj())),
320                CPLXSXP => {
321                    Rany::Complexes(std::mem::transmute::<&Robj, &Complexes>(self.as_robj()))
322                }
323                STRSXP => Rany::Strings(std::mem::transmute::<&Robj, &Strings>(self.as_robj())),
324                DOTSXP => Rany::Dot(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
325                ANYSXP => Rany::Any(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
326                VECSXP => Rany::List(std::mem::transmute::<&Robj, &List>(self.as_robj())),
327                EXPRSXP => {
328                    Rany::Expressions(std::mem::transmute::<&Robj, &Expressions>(self.as_robj()))
329                }
330                BCODESXP => Rany::Bytecode(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
331                EXTPTRSXP => Rany::ExternalPtr(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
332                WEAKREFSXP => Rany::WeakRef(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
333                RAWSXP => Rany::Raw(std::mem::transmute::<&Robj, &Raw>(self.as_robj())),
334                #[cfg(not(use_objsxp))]
335                S4SXP => Rany::S4(std::mem::transmute(self.as_robj())),
336                #[cfg(use_objsxp)]
337                OBJSXP => Rany::S4(std::mem::transmute::<&Robj, &S4>(self.as_robj())),
338                _ => Rany::Unknown(std::mem::transmute::<&Robj, &Robj>(self.as_robj())),
339            }
340        }
341    }
342}
343
344impl Types for Robj {}
345
346impl Robj {
347    /// Is this object is an `NA` scalar?
348    /// Works for character, integer and numeric types.
349    ///
350    /// ```
351    /// use extendr_api::prelude::*;
352    /// test! {
353    ///
354    /// assert_eq!(r!(NA_INTEGER).is_na(), true);
355    /// assert_eq!(r!(NA_REAL).is_na(), true);
356    /// assert_eq!(r!(NA_STRING).is_na(), true);
357    /// }
358    /// ```
359    pub fn is_na(&self) -> bool {
360        if self.len() != 1 {
361            false
362        } else {
363            unsafe {
364                let sexp = self.get();
365                use SEXPTYPE::*;
366                match self.sexptype() {
367                    STRSXP => STRING_ELT(sexp, 0) == extendr_ffi::R_NaString,
368                    INTSXP => *(INTEGER(sexp)) == extendr_ffi::R_NaInt,
369                    LGLSXP => *(LOGICAL(sexp)) == extendr_ffi::R_NaInt,
370                    REALSXP => R_IsNA(*(REAL(sexp))) != 0,
371                    CPLXSXP => R_IsNA((*COMPLEX(sexp)).r) != 0,
372                    // a character vector contains `CHARSXP`, and thus you
373                    // seldom have `Robj`'s that are `CHARSXP` themselves
374                    CHARSXP => sexp == extendr_ffi::R_NaString,
375                    _ => false,
376                }
377            }
378        }
379    }
380
381    /// Get a read-only reference to the content of an integer vector.
382    /// ```
383    /// use extendr_api::prelude::*;
384    /// test! {
385    ///
386    /// let robj = r!([1, 2, 3]);
387    /// assert_eq!(robj.as_integer_slice().unwrap(), [1, 2, 3]);
388    /// }
389    /// ```
390    pub fn as_integer_slice<'a>(&self) -> Option<&'a [i32]> {
391        self.as_typed_slice()
392    }
393
394    /// Convert an [`Robj`] into [`Integers`].
395    pub fn as_integers(&self) -> Option<Integers> {
396        self.clone().try_into().ok()
397    }
398
399    /// Get a `Vec<i32>` copied from the object.
400    ///
401    /// ```
402    /// use extendr_api::prelude::*;
403    /// test! {
404    ///
405    /// let robj = r!([1, 2, 3]);
406    /// assert_eq!(robj.as_integer_slice().unwrap(), vec![1, 2, 3]);
407    /// }
408    /// ```
409    pub fn as_integer_vector(&self) -> Option<Vec<i32>> {
410        self.as_integer_slice().map(|value| value.to_vec())
411    }
412
413    /// Get a read-only reference to the content of a logical vector
414    /// using the tri-state [Rbool]. Returns None if not a logical vector.
415    /// ```
416    /// use extendr_api::prelude::*;
417    /// test! {
418    ///     let robj = r!([TRUE, FALSE]);
419    ///     assert_eq!(robj.as_logical_slice().unwrap(), [TRUE, FALSE]);
420    /// }
421    /// ```
422    pub fn as_logical_slice(&self) -> Option<&[Rbool]> {
423        self.as_typed_slice()
424    }
425
426    /// Get a `Vec<Rbool>` copied from the object
427    /// using the tri-state [`Rbool`].
428    /// Returns `None` if not a logical vector.
429    ///
430    /// ```
431    /// use extendr_api::prelude::*;
432    /// test! {
433    ///     let robj = r!([TRUE, FALSE]);
434    ///     assert_eq!(robj.as_logical_vector().unwrap(), vec![TRUE, FALSE]);
435    /// }
436    /// ```
437    pub fn as_logical_vector(&self) -> Option<Vec<Rbool>> {
438        self.as_logical_slice().map(|value| value.to_vec())
439    }
440
441    /// Get an iterator over logical elements of this slice.
442    /// ```
443    /// use extendr_api::prelude::*;
444    /// test! {
445    ///     let robj = r!([TRUE, FALSE, NA_LOGICAL]);
446    ///     let mut num_na = 0;
447    ///     for val in robj.as_logical_iter().unwrap() {
448    ///       if val.is_na() {
449    ///           num_na += 1;
450    ///       }
451    ///     }
452    ///     assert_eq!(num_na, 1);
453    /// }
454    /// ```
455    pub fn as_logical_iter(&self) -> Option<impl Iterator<Item = &Rbool>> {
456        self.as_logical_slice().map(|slice| slice.iter())
457    }
458
459    /// Get a read-only reference to the content of a double vector.
460    /// Note: the slice may contain NaN or NA values.
461    /// We may introduce a "Real" type to handle this like the Rbool type.
462    /// ```
463    /// use extendr_api::prelude::*;
464    /// test! {
465    ///     let robj = r!([Some(1.), None, Some(3.)]);
466    ///     let mut tot = 0.;
467    ///     for val in robj.as_real_slice().unwrap() {
468    ///       if !val.is_na() {
469    ///         tot += val;
470    ///       }
471    ///     }
472    ///     assert_eq!(tot, 4.);
473    /// }
474    /// ```
475    pub fn as_real_slice(&self) -> Option<&[f64]> {
476        self.as_typed_slice()
477    }
478
479    /// Get an iterator over real elements of this slice.
480    ///
481    /// ```
482    /// use extendr_api::prelude::*;
483    /// test! {
484    ///     let robj = r!([1., 2., 3.]);
485    ///     let mut tot = 0.;
486    ///     for val in robj.as_real_iter().unwrap() {
487    ///       if !val.is_na() {
488    ///         tot += val;
489    ///       }
490    ///     }
491    ///     assert_eq!(tot, 6.);
492    /// }
493    /// ```
494    pub fn as_real_iter(&self) -> Option<impl Iterator<Item = &f64>> {
495        self.as_real_slice().map(|slice| slice.iter())
496    }
497
498    /// Get a `Vec<f64>` copied from the object.
499    ///
500    /// ```
501    /// use extendr_api::prelude::*;
502    /// test! {
503    ///     let robj = r!([1., 2., 3.]);
504    ///     assert_eq!(robj.as_real_vector().unwrap(), vec![1., 2., 3.]);
505    /// }
506    /// ```
507    pub fn as_real_vector(&self) -> Option<Vec<f64>> {
508        self.as_real_slice().map(|value| value.to_vec())
509    }
510
511    /// Get a read-only reference to the content of an integer or logical vector.
512    /// ```
513    /// use extendr_api::prelude::*;
514    /// test! {
515    ///     let robj = r!(Raw::from_bytes(&[1, 2, 3]));
516    ///     assert_eq!(robj.as_raw_slice().unwrap(), &[1, 2, 3]);
517    /// }
518    /// ```
519    pub fn as_raw_slice(&self) -> Option<&[u8]> {
520        self.as_typed_slice()
521    }
522
523    /// Get a read-write reference to the content of an integer or logical vector.
524    /// Note that rust slices are 0-based so `slice[1]` is the middle value.
525    /// ```
526    /// use extendr_api::prelude::*;
527    /// test! {
528    ///     let mut robj = r!([1, 2, 3]);
529    ///     let slice : & mut [i32] = robj.as_integer_slice_mut().unwrap();
530    ///     slice[1] = 100;
531    ///     assert_eq!(robj, r!([1, 100, 3]));
532    /// }
533    /// ```
534    pub fn as_integer_slice_mut(&mut self) -> Option<&mut [i32]> {
535        self.as_typed_slice_mut()
536    }
537
538    /// Get a read-write reference to the content of a double vector.
539    /// Note that rust slices are 0-based so `slice[1]` is the middle value.
540    /// ```
541    /// use extendr_api::prelude::*;
542    /// test! {
543    ///     let mut robj = r!([1.0, 2.0, 3.0]);
544    ///     let slice = robj.as_real_slice_mut().unwrap();
545    ///     slice[1] = 100.0;
546    ///     assert_eq!(robj, r!([1.0, 100.0, 3.0]));
547    /// }
548    /// ```
549    pub fn as_real_slice_mut(&mut self) -> Option<&mut [f64]> {
550        self.as_typed_slice_mut()
551    }
552
553    /// Get a read-write reference to the content of a raw vector.
554    /// ```
555    /// use extendr_api::prelude::*;
556    /// test! {
557    ///     let mut robj = r!(Raw::from_bytes(&[1, 2, 3]));
558    ///     let slice = robj.as_raw_slice_mut().unwrap();
559    ///     slice[1] = 100;
560    ///     assert_eq!(robj, r!(Raw::from_bytes(&[1, 100, 3])));
561    /// }
562    /// ```
563    pub fn as_raw_slice_mut(&mut self) -> Option<&mut [u8]> {
564        self.as_typed_slice_mut()
565    }
566
567    /// Get a vector of owned strings.
568    /// Owned strings have long lifetimes, but are much slower than references.
569    /// ```
570    /// use extendr_api::prelude::*;
571    /// test! {
572    ///    let robj1 = Robj::from("xyz");
573    ///    assert_eq!(robj1.as_string_vector(), Some(vec!["xyz".to_string()]));
574    ///    let robj2 = Robj::from(1);
575    ///    assert_eq!(robj2.as_string_vector(), None);
576    /// }
577    /// ```
578    pub fn as_string_vector(&self) -> Option<Vec<String>> {
579        self.as_str_iter()
580            .map(|iter| iter.map(str::to_string).collect())
581    }
582
583    /// Get a vector of string references.
584    /// String references (&str) are faster, but have short lifetimes.
585    /// ```
586    /// use extendr_api::prelude::*;
587    /// test! {
588    ///    let robj1 = Robj::from("xyz");
589    ///    assert_eq!(robj1.as_str_vector(), Some(vec!["xyz"]));
590    ///    let robj2 = Robj::from(1);
591    ///    assert_eq!(robj2.as_str_vector(), None);
592    /// }
593    /// ```
594    pub fn as_str_vector(&self) -> Option<Vec<&str>> {
595        self.as_str_iter().map(|iter| iter.collect())
596    }
597
598    /// Get a read-only reference to a scalar string type.
599    /// ```
600    /// use extendr_api::prelude::*;
601    /// test! {
602    ///    let robj1 = Robj::from("xyz");
603    ///    let robj2 = Robj::from(1);
604    ///    assert_eq!(robj1.as_str(), Some("xyz"));
605    ///    assert_eq!(robj2.as_str(), None);
606    /// }
607    /// ```
608    pub fn as_str<'a>(&self) -> Option<&'a str> {
609        unsafe {
610            let charsxp = match self.sexptype() {
611                STRSXP => {
612                    // only allows scalar strings
613                    if self.len() != 1 {
614                        return None;
615                    }
616                    STRING_ELT(self.get(), 0)
617                }
618                CHARSXP => self.get(),
619                SYMSXP => PRINTNAME(self.get()),
620                _ => return None,
621            };
622            rstr::charsxp_to_str(charsxp)
623        }
624    }
625
626    /// Get a scalar integer.
627    /// ```
628    /// use extendr_api::prelude::*;
629    /// test! {
630    ///    let robj1 = Robj::from("xyz");
631    ///    let robj2 = Robj::from(1);
632    ///    let robj3 = Robj::from(NA_INTEGER);
633    ///    assert_eq!(robj1.as_integer(), None);
634    ///    assert_eq!(robj2.as_integer(), Some(1));
635    ///    assert_eq!(robj3.as_integer(), None);
636    /// }
637    /// ```
638    pub fn as_integer(&self) -> Option<i32> {
639        match self.as_integer_slice() {
640            Some(slice) if slice.len() == 1 && !slice[0].is_na() => Some(slice[0]),
641            _ => None,
642        }
643    }
644
645    /// Get a scalar real.
646    /// ```
647    /// use extendr_api::prelude::*;
648    /// test! {
649    ///    let robj1 = Robj::from(1);
650    ///    let robj2 = Robj::from(1.);
651    ///    let robj3 = Robj::from(NA_REAL);
652    ///    assert_eq!(robj1.as_real(), None);
653    ///    assert_eq!(robj2.as_real(), Some(1.));
654    ///    assert_eq!(robj3.as_real(), None);
655    /// }
656    /// ```
657    pub fn as_real(&self) -> Option<f64> {
658        match self.as_real_slice() {
659            Some(slice) if slice.len() == 1 && !slice[0].is_na() => Some(slice[0]),
660            _ => None,
661        }
662    }
663
664    /// Get a scalar rust boolean.
665    /// ```
666    /// use extendr_api::prelude::*;
667    /// test! {
668    ///    let robj1 = Robj::from(TRUE);
669    ///    let robj2 = Robj::from(1.);
670    ///    let robj3 = Robj::from(NA_LOGICAL);
671    ///    assert_eq!(robj1.as_bool(), Some(true));
672    ///    assert_eq!(robj2.as_bool(), None);
673    ///    assert_eq!(robj3.as_bool(), None);
674    /// }
675    /// ```
676    pub fn as_bool(&self) -> Option<bool> {
677        match self.as_logical_slice() {
678            Some(slice) if slice.len() == 1 && !slice[0].is_na() => Some(slice[0].is_true()),
679            _ => None,
680        }
681    }
682
683    /// Get a scalar boolean as a tri-boolean [Rbool] value.
684    /// ```
685    /// use extendr_api::prelude::*;
686    /// test! {
687    ///    let robj1 = Robj::from(TRUE);
688    ///    let robj2 = Robj::from([TRUE, FALSE]);
689    ///    let robj3 = Robj::from(NA_LOGICAL);
690    ///    assert_eq!(robj1.as_logical(), Some(TRUE));
691    ///    assert_eq!(robj2.as_logical(), None);
692    ///    assert_eq!(robj3.as_logical().unwrap().is_na(), true);
693    /// }
694    /// ```
695    pub fn as_logical(&self) -> Option<Rbool> {
696        match self.as_logical_slice() {
697            Some(slice) if slice.len() == 1 => Some(slice[0]),
698            _ => None,
699        }
700    }
701}
702
703pub trait Eval: GetSexp {
704    /// Evaluate the expression in R and return an error or an R object.
705    /// ```
706    /// use extendr_api::prelude::*;
707    /// test! {
708    ///
709    ///    let add = lang!("+", 1, 2);
710    ///    assert_eq!(add.eval().unwrap(), r!(3));
711    /// }
712    /// ```
713    fn eval(&self) -> Result<Robj> {
714        self.eval_with_env(&global_env())
715    }
716
717    /// Evaluate the expression in R and return an error or an R object.
718    /// ```
719    /// use extendr_api::prelude::*;
720    /// test! {
721    ///
722    ///    let add = lang!("+", 1, 2);
723    ///    assert_eq!(add.eval_with_env(&global_env()).unwrap(), r!(3));
724    /// }
725    /// ```
726    fn eval_with_env(&self, env: &Environment) -> Result<Robj> {
727        single_threaded(|| unsafe {
728            let mut error: raw::c_int = 0;
729            let res = R_tryEval(self.get(), env.get(), &mut error as *mut raw::c_int);
730            if error != 0 {
731                Err(Error::EvalError(Robj::from_sexp(self.get())))
732            } else {
733                Ok(Robj::from_sexp(res))
734            }
735        })
736    }
737
738    /// Evaluate the expression and return NULL or an R object.
739    /// ```
740    /// use extendr_api::prelude::*;
741    /// test! {
742    ///    let bad = lang!("imnotavalidfunctioninR", 1, 2);
743    ///    assert_eq!(bad.eval_blind(), r!(NULL));
744    /// }
745    /// ```
746    fn eval_blind(&self) -> Robj {
747        let res = self.eval();
748        if let Ok(robj) = res {
749            robj
750        } else {
751            Robj::from(())
752        }
753    }
754}
755
756impl Eval for Robj {}
757
758/// Generic access to typed slices in an Robj.
759pub trait AsTypedSlice<'a, T>
760where
761    Self: 'a,
762{
763    fn as_typed_slice(&self) -> Option<&'a [T]>
764    where
765        Self: 'a,
766    {
767        None
768    }
769
770    fn as_typed_slice_mut(&mut self) -> Option<&'a mut [T]>
771    where
772        Self: 'a,
773    {
774        None
775    }
776}
777
778macro_rules! make_typed_slice {
779    ($type: ty, $fn: tt, $($sexp: tt),* ) => {
780        impl<'a> AsTypedSlice<'a, $type> for Robj
781        where
782            Self : 'a,
783        {
784            fn as_typed_slice(&self) -> Option<&'a [$type]> {
785                match self.sexptype() {
786                    $( $sexp )|* => {
787                        unsafe {
788                            // if the vector is empty return an empty slice
789                            if self.is_empty() {
790                                return Some(&[])
791                            }
792                            // otherwise get the slice
793                            let ptr = $fn(self.get()) as *const $type;
794                            Some(std::slice::from_raw_parts(ptr, self.len()))
795                        }
796                    }
797                    _ => None
798                }
799            }
800
801            fn as_typed_slice_mut(&mut self) -> Option<&'a mut [$type]> {
802                match self.sexptype() {
803                    $( $sexp )|* => {
804                        unsafe {
805                            if self.is_empty() {
806                                return Some(&mut []);
807                            }
808                            let ptr = $fn(self.get_mut()) as *mut $type;
809
810                            Some(std::slice::from_raw_parts_mut(ptr, self.len()))
811
812                        }
813                    }
814                    _ => None
815                }
816            }
817        }
818    }
819}
820
821make_typed_slice!(Rbool, INTEGER, LGLSXP);
822make_typed_slice!(i32, INTEGER, INTSXP);
823make_typed_slice!(Rint, INTEGER, INTSXP);
824make_typed_slice!(f64, REAL, REALSXP);
825make_typed_slice!(Rfloat, REAL, REALSXP);
826make_typed_slice!(u8, RAW, RAWSXP);
827make_typed_slice!(Rstr, STRING_PTR_RO, STRSXP);
828make_typed_slice!(c64, COMPLEX, CPLXSXP);
829make_typed_slice!(Rcplx, COMPLEX, CPLXSXP);
830make_typed_slice!(Rcomplex, COMPLEX, CPLXSXP);
831
832/// Provides access to the attributes of an R object.
833///
834/// The `Attribute` trait provides a consistent interface to getting, setting, and checking for the presence of attributes in an R object.
835///
836#[allow(non_snake_case)]
837pub trait Attributes: Types + Length {
838    /// Get a specific attribute as a borrowed `Robj` if it exists.
839    /// ```
840    /// use extendr_api::prelude::*;
841    /// test! {
842    ///    let mut robj = r!("hello");
843    ///    robj.set_attrib(sym!(xyz), 1);
844    ///    assert_eq!(robj.get_attrib(sym!(xyz)), Some(r!(1)));
845    /// }
846    /// ```
847    fn get_attrib<'a, N>(&self, name: N) -> Option<Robj>
848    where
849        Self: 'a,
850        Robj: From<N> + 'a,
851    {
852        let name = Robj::from(name);
853        if self.sexptype() == SEXPTYPE::CHARSXP {
854            None
855        } else {
856            // FIXME: this attribute does not need protection
857            let res = unsafe { Robj::from_sexp(Rf_getAttrib(self.get(), name.get())) };
858            if res.is_null() {
859                None
860            } else {
861                Some(res)
862            }
863        }
864    }
865
866    /// Return true if an attribute exists.
867    fn has_attrib<'a, N>(&self, name: N) -> bool
868    where
869        Self: 'a,
870        Robj: From<N> + 'a,
871    {
872        let name = Robj::from(name);
873        if self.sexptype() == SEXPTYPE::CHARSXP {
874            false
875        } else {
876            unsafe { Rf_getAttrib(self.get(), name.get()) != R_NilValue }
877        }
878    }
879
880    /// Set a specific attribute in-place and return the object.
881    ///
882    /// Note that some combinations of attributes are illegal and this will
883    /// return an error.
884    /// ```
885    /// use extendr_api::prelude::*;
886    /// test! {
887    ///    let mut robj = r!("hello");
888    ///    robj.set_attrib(sym!(xyz), 1)?;
889    ///    assert_eq!(robj.get_attrib(sym!(xyz)), Some(r!(1)));
890    /// }
891    /// ```
892    fn set_attrib<N, V>(&mut self, name: N, value: V) -> Result<&mut Self>
893    where
894        N: Into<Robj>,
895        V: Into<Robj>,
896    {
897        let name = name.into();
898        let value = value.into();
899        unsafe {
900            let sexp = self.get_mut();
901            let result =
902                single_threaded(|| catch_r_error(|| Rf_setAttrib(sexp, name.get(), value.get())));
903            result.map(|_| self)
904        }
905    }
906
907    /// Get the `names` attribute as a string iterator if one exists.
908    /// ```
909    /// use extendr_api::prelude::*;
910    /// test! {
911    ///    let list = list!(a = 1, b = 2, c = 3);
912    ///    let names : Vec<_> = list.names().unwrap().collect();
913    ///    assert_eq!(names, vec!["a", "b", "c"]);
914    /// }
915    /// ```
916    fn names(&self) -> Option<StrIter> {
917        if let Some(names) = self.get_attrib(wrapper::symbol::names_symbol()) {
918            names.as_str_iter()
919        } else {
920            None
921        }
922    }
923
924    /// Return true if this object has an attribute called `names`.
925    fn has_names(&self) -> bool {
926        self.has_attrib(wrapper::symbol::names_symbol())
927    }
928
929    /// Set the `names` attribute from a string iterator.
930    ///
931    /// Returns `Error::NamesLengthMismatch` if the length of the names does
932    /// not match the length of the object.
933    ///
934    /// ```
935    /// use extendr_api::prelude::*;
936    /// test! {
937    ///     let mut obj = r!([1, 2, 3]);
938    ///     obj.set_names(&["a", "b", "c"]).unwrap();
939    ///     assert_eq!(obj.names().unwrap().collect::<Vec<_>>(), vec!["a", "b", "c"]);
940    ///     assert_eq!(r!([1, 2, 3]).set_names(&["a", "b"]), Err(Error::NamesLengthMismatch(r!(["a", "b"]))));
941    /// }
942    /// ```
943    fn set_names<T>(&mut self, names: T) -> Result<&mut Self>
944    where
945        T: IntoIterator,
946        T::IntoIter: ExactSizeIterator,
947        T::Item: ToVectorValue + AsRef<str>,
948    {
949        let iter = names.into_iter();
950        let robj = iter.collect_robj();
951        if !robj.is_vector() && !robj.is_pairlist() {
952            Err(Error::ExpectedVector(robj))
953        } else if robj.len() != self.len() {
954            Err(Error::NamesLengthMismatch(robj))
955        } else {
956            self.set_attrib(wrapper::symbol::names_symbol(), robj)
957        }
958    }
959
960    /// Get the `dim` attribute as an integer iterator if one exists.
961    /// ```
962    /// use extendr_api::prelude::*;
963    /// test! {
964    ///
965    ///    let array = R!(r#"array(data = c(1, 2, 3, 4), dim = c(2, 2), dimnames = list(c("x", "y"), c("a","b")))"#).unwrap();
966    ///    let dim : Vec<_> = array.dim().unwrap().iter().collect();
967    ///    assert_eq!(dim, vec![2, 2]);
968    /// }
969    /// ```
970    fn dim(&self) -> Option<Integers> {
971        if let Some(dim) = self.get_attrib(wrapper::symbol::dim_symbol()) {
972            dim.as_integers()
973        } else {
974            None
975        }
976    }
977
978    /// Get the `dimnames` attribute as a list iterator if one exists.
979    /// ```
980    /// use extendr_api::prelude::*;
981    /// test! {
982    ///    let array = R!(r#"array(data = c(1, 2, 3, 4), dim = c(2, 2), dimnames = list(c("x", "y"), c("a","b")))"#).unwrap();
983    ///    let names : Vec<_> = array.dimnames().unwrap().collect();
984    ///    assert_eq!(names, vec![r!(["x", "y"]), r!(["a", "b"])]);
985    /// }
986    /// ```
987    fn dimnames(&self) -> Option<ListIter> {
988        if let Some(names) = self.get_attrib(wrapper::symbol::dimnames_symbol()) {
989            names.as_list().map(|v| v.values())
990        } else {
991            None
992        }
993    }
994
995    /// Get the `class` attribute as a string iterator if one exists.
996    /// ```
997    /// use extendr_api::prelude::*;
998    /// test! {
999    ///    let formula = R!("y ~ A * x + b").unwrap();
1000    ///    let class : Vec<_> = formula.class().unwrap().collect();
1001    ///    assert_eq!(class, ["formula"]);
1002    /// }
1003    /// ```
1004    fn class(&self) -> Option<StrIter> {
1005        if let Some(class) = self.get_attrib(wrapper::symbol::class_symbol()) {
1006            class.as_str_iter()
1007        } else {
1008            None
1009        }
1010    }
1011
1012    /// Set the `class` attribute from a string iterator, and return the same
1013    /// object.
1014    ///
1015    /// May return an error for some class names.
1016    /// ```
1017    /// use extendr_api::prelude::*;
1018    /// test! {
1019    ///     let mut obj = r!([1, 2, 3]);
1020    ///     obj.set_class(&["a", "b", "c"])?;
1021    ///     assert_eq!(obj.class().unwrap().collect::<Vec<_>>(), vec!["a", "b", "c"]);
1022    ///     assert_eq!(obj.inherits("a"), true);
1023    /// }
1024    /// ```
1025    fn set_class<T>(&mut self, class: T) -> Result<&mut Self>
1026    where
1027        T: IntoIterator,
1028        T::IntoIter: ExactSizeIterator,
1029        T::Item: ToVectorValue + AsRef<str>,
1030    {
1031        let iter = class.into_iter();
1032        self.set_attrib(wrapper::symbol::class_symbol(), iter.collect_robj())
1033    }
1034
1035    /// Return true if this object has this class attribute.
1036    /// Implicit classes are not supported.
1037    /// ```
1038    /// use extendr_api::prelude::*;
1039    /// test! {
1040    ///    let formula = R!("y ~ A * x + b").unwrap();
1041    ///    assert_eq!(formula.inherits("formula"), true);
1042    /// }
1043    /// ```
1044    fn inherits(&self, classname: &str) -> bool {
1045        if let Some(mut iter) = self.class() {
1046            iter.any(|n| n == classname)
1047        } else {
1048            false
1049        }
1050    }
1051
1052    /// Get the `levels` attribute as a string iterator if one exists.
1053    /// ```
1054    /// use extendr_api::prelude::*;
1055    /// test! {
1056    ///    let factor = factor!(vec!["abcd", "def", "fg", "fg"]);
1057    ///    let levels : Vec<_> = factor.levels().unwrap().collect();
1058    ///    assert_eq!(levels, vec!["abcd", "def", "fg"]);
1059    /// }
1060    /// ```
1061    fn levels(&self) -> Option<StrIter> {
1062        if let Some(levels) = self.get_attrib(wrapper::symbol::levels_symbol()) {
1063            levels.as_str_iter()
1064        } else {
1065            None
1066        }
1067    }
1068}
1069
1070impl Attributes for Robj {}
1071
1072/// Compare equality with integer slices.
1073impl PartialEq<[i32]> for Robj {
1074    fn eq(&self, rhs: &[i32]) -> bool {
1075        self.as_integer_slice() == Some(rhs)
1076    }
1077}
1078
1079/// Compare equality with slices of double.
1080impl PartialEq<[f64]> for Robj {
1081    fn eq(&self, rhs: &[f64]) -> bool {
1082        self.as_real_slice() == Some(rhs)
1083    }
1084}
1085
1086/// Compare equality with strings.
1087impl PartialEq<str> for Robj {
1088    fn eq(&self, rhs: &str) -> bool {
1089        self.as_str() == Some(rhs)
1090    }
1091}
1092
1093/// Compare equality with two Robjs.
1094impl PartialEq<Robj> for Robj {
1095    fn eq(&self, rhs: &Robj) -> bool {
1096        unsafe {
1097            if self.get() == rhs.get() {
1098                return true;
1099            }
1100
1101            // see https://github.com/hadley/r-internals/blob/master/misc.md
1102            R_compute_identical(self.get(), rhs.get(), 16) != Rboolean::FALSE
1103        }
1104    }
1105}
1106
1107/// Release any owned objects.
1108impl Drop for Robj {
1109    fn drop(&mut self) {
1110        unsafe {
1111            ownership::unprotect(self.inner);
1112        }
1113    }
1114}