Struct extendr_api::wrapper::function::Function

pub struct Function { /* fields omitted */ }

Wrapper for creating functions (CLOSSXP).

use extendr_api::prelude::*;
test! {
    // Closures are functions.
    let expr = R!("function(a = 1, b) {c <- a + b}")?;
    let func = expr.as_function().unwrap();

    let expected_formals = Pairlist::from_pairs(vec![("a", r!(1.0)), ("b", missing_arg().into())]);
    let expected_body = lang!(
        "{", lang!("<-", sym!(c), lang!("+", sym!(a), sym!(b))));
    assert_eq!(func.formals().unwrap(), expected_formals);
    assert_eq!(func.body().unwrap(), expected_body);
    assert_eq!(func.environment().unwrap(), global_env());

    // Primitives can also be functions.
    let expr = R!("`~`")?;
    let func = expr.as_function().unwrap();
    assert_eq!(func.formals(), None);
    assert_eq!(func.body(), None);
    assert_eq!(func.environment(), None);
}

Implementations

impl Function

pub fn from_parts(
    formals: Pairlist,
    body: Language,
    env: Environment
) -> Result<Self>

Make a function from parts.

use extendr_api::prelude::*;
test! {
    let formals = pairlist!(a=NULL);
    let body = lang!("+", sym!(a), r!(1)).try_into()?;
    let env = global_env();
    let f = r!(Function::from_parts(formals, body, env )?);
    assert_eq!(f.call(pairlist!(a=1))?, r!(2));
}

pub fn call(&self, args: Pairlist) -> Result<Robj>

Do the equivalent of x(a, b, c)

use extendr_api::prelude::*;
test! {
    let function = R!("function(a, b) a + b").unwrap().as_function().unwrap();
    assert_eq!(function.call(pairlist!(a=1, b=2)).unwrap(), r!(3));
}

pub fn formals(&self) -> Option<Pairlist>

Get the formal arguments of the function or None if it is a primitive.

pub fn body(&self) -> Option<Robj>

Get the body of the function or None if it is a primitive.

pub fn environment(&self) -> Option<Environment>

Get the environment of the function or None if it is a primitive.

Trait Implementations

impl Clone for Function

fn clone(&self) -> Function

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Conversions for Function

as_*()

fn as_symbol(&self) -> Option<Symbol>

Convert a symbol object to a Symbol wrapper.

fn as_char(&self) -> Option<Rstr>

Convert a CHARSXP object to a Rstr wrapper.

fn as_raw(&self) -> Option<Raw>

Convert a raw object to a Rstr wrapper.

fn as_language(&self) -> Option<Language>

Convert a language object to a Language wrapper.

fn as_pairlist(&self) -> Option<Pairlist>

Convert a pair list object (LISTSXP) to a Pairlist wrapper.

fn as_list(&self) -> Option<List>

Convert a list object (VECSXP) to a List wrapper.

fn as_expressions(&self) -> Option<Expressions>

Convert an expression object (EXPRSXP) to a Expr wrapper.

fn as_environment(&self) -> Option<Environment>

Convert an environment object (ENVSXP) to a Env wrapper.

fn as_function(&self) -> Option<Function>

Convert a function object (CLOSXP) to a Function wrapper.

fn as_promise(&self) -> Option<Promise>

Get a wrapper for a promise.

impl Debug for Function

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Function> for Robj

fn from(val: Function) -> Self

Make an robj from a wrapper.

impl<'a> FromRobj<'a> for Function

fn from_robj(robj: &'a Robj) -> Result<Self, &'static str>

impl GetSexp for Function

unsafe fn get(&self) -> SEXP

Get a copy of the underlying SEXP.

fn as_robj(&self) -> &Robj

Get a reference to a Robj for this type.

fn as_robj_mut(&mut self) -> &mut Robj

Get a mutable reference to a Robj for this type.

impl Length for Function

len() and is_empty()

fn len(&self) -> usize

Get the extended length of the object.

fn is_empty(&self) -> bool

Returns true if the Robj contains no elements.

impl Operators for Function

dollar() etc.

fn dollar<T>(&self, symbol: T) -> Result<Robj> where
    T: AsRef<str>, 

Do the equivalent of x$y

fn slice<T>(&self, rhs: T) -> Result<Robj> where
    T: Into<Robj>, 

Do the equivalent of x[y]

fn index<T>(&self, rhs: T) -> Result<Robj> where
    T: Into<Robj>, 

Do the equivalent of x[[y]]

fn tilde<T>(&self, rhs: T) -> Result<Robj> where
    T: Into<Robj>, 

Do the equivalent of x ~ y

fn double_colon<T>(&self, rhs: T) -> Result<Robj> where
    T: Into<Robj>, 

Do the equivalent of x :: y

fn call(&self, args: Pairlist) -> Result<Robj>

Do the equivalent of x(a, b, c)

impl PartialEq<Function> for Function

fn eq(&self, other: &Function) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Function) -> bool

This method tests for !=.

impl Rinternals for Function

find_var() etc.

fn is_null(&self) -> bool

Return true if this is the null object.

fn is_symbol(&self) -> bool

Return true if this is a symbol.

fn is_logical(&self) -> bool

Return true if this is a boolean (logical) vector

fn is_real(&self) -> bool

Return true if this is a real (f64) vector.

fn is_complex(&self) -> bool

Return true if this is a complex vector.

fn is_expressions(&self) -> bool

Return true if this is an expression.

fn is_environment(&self) -> bool

Return true if this is an environment.

fn is_promise(&self) -> bool

Return true if this is an environment.

fn is_string(&self) -> bool

Return true if this is a string.

fn is_object(&self) -> bool

Return true if this is an object (ie. has a class attribute).

fn is_s4(&self) -> bool

Return true if this is a S4 object.

fn is_external_pointer(&self) -> bool

Return true if this is an expression.

fn get_current_srcref(val: i32) -> Robj

Get the source ref.

fn get_src_filename(&self) -> Robj

Get the source filename.

fn as_character_vector(&self) -> Robj

Convert to a string vector.

fn coerce_vector(&self, sexptype: u32) -> Robj

Convert to vectors of many kinds.

fn pair_to_vector_list(&self) -> Robj

Convert a pairlist (LISTSXP) to a vector list (VECSXP).

fn vector_to_pair_list(&self) -> Robj

Convert a vector list (VECSXP) to a pair list (LISTSXP)

fn as_character_factor(&self) -> Robj

Convert a factor to a string vector.

fn alloc_matrix(sexptype: SEXPTYPE, rows: i32, cols: i32) -> Robj

Allocate a matrix object.

fn duplicate(&self) -> Robj

Do a deep copy of this object. Note that clone() only adds a reference.

fn find_function<K: TryInto<Symbol, Error = Error>>(
    &self,
    key: K
) -> Result<Robj>

Find a function in an environment ignoring other variables.

fn find_var<K: TryInto<Symbol, Error = Error>>(&self, key: K) -> Result<Robj>

Find a variable in an environment.

fn eval_promise(&self) -> Result<Robj>

If this object is a promise, evaluate it, otherwise return the object.

fn ncols(&self) -> usize

Number of columns of a matrix

fn nrows(&self) -> usize

Number of rows of a matrix

fn xlengthgets(&self, new_len: usize) -> Result<Robj>

Copy a vector and resize it. See. https://github.com/hadley/r-internals/blob/master/vectors.md

fn alloc_vector(sexptype: u32, len: usize) -> Robj

Allocated an owned object of a certain type.

fn conformable(a: &Robj, b: &Robj) -> bool

Return true if two arrays have identical dims.

fn is_array(&self) -> bool

Return true if this is an array.

fn is_factor(&self) -> bool

Return true if this is factor.

fn is_frame(&self) -> bool

Return true if this is a data frame.

fn is_function(&self) -> bool

Return true if this is a function or a primitive (CLOSXP, BUILTINSXP or SPECIALSXP)

fn is_integer(&self) -> bool

Return true if this is an integer vector (INTSXP) but not a factor.

fn is_language(&self) -> bool

Return true if this is a language object (LANGSXP).

fn is_pairlist(&self) -> bool

Return true if this is NILSXP or LISTSXP.

fn is_matrix(&self) -> bool

Return true if this is a matrix.

fn is_list(&self) -> bool

Return true if this is NILSXP or VECSXP.

fn is_number(&self) -> bool

Return true if this is INTSXP, LGLSXP or REALSXP but not a factor.

fn is_primitive(&self) -> bool

Return true if this is a primitive function BUILTINSXP, SPECIALSXP.

fn is_ts(&self) -> bool

Return true if this is a time series vector (see tsp).

fn is_user_binop(&self) -> bool

Return true if this is a user defined binop.

fn is_valid_string(&self) -> bool

Return true if this is a valid string.

fn is_valid_string_f(&self) -> bool

Return true if this is a valid string.

fn is_vector(&self) -> bool

Return true if this is a vector.

fn is_vector_atomic(&self) -> bool

Return true if this is an atomic vector.

fn is_vector_list(&self) -> bool

Return true if this is a vector list.

fn is_vectorizable(&self) -> bool

Return true if this is can be made into a vector.

fn is_raw(&self) -> bool

Return true if this is RAWSXP.

fn is_char(&self) -> bool

Return true if this is CHARSXP.

fn is_missing_arg(&self) -> bool

fn is_unbound_value(&self) -> bool

fn is_package_env(&self) -> bool

fn package_env_name(&self) -> Robj

fn is_namespace_env(&self) -> bool

fn namespace_env_spec(&self) -> Robj

fn is_altrep(&self) -> bool

Returns true if this is an ALTREP object.

fn is_altinteger(&self) -> bool

Returns true if this is an integer ALTREP object.

fn is_altreal(&self) -> bool

Returns true if this is an real ALTREP object.

fn is_altlogical(&self) -> bool

Returns true if this is an logical ALTREP object.

fn is_altraw(&self) -> bool

Returns true if this is a raw ALTREP object.

fn is_altstring(&self) -> bool

Returns true if this is an integer ALTREP object.

fn deparse(&self) -> Result<String>

Generate a text representation of this object.

impl Serialize for Function

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
    S: Serializer, 

Serialize this value into the given Serde serializer.

impl Slices for Function

as_typed_slice_raw() etc.

unsafe fn as_typed_slice_raw<T>(&self) -> &[T]

Get an immutable slice to this object’s data.

unsafe fn as_typed_slice_raw_mut<T>(&mut self) -> &mut [T]

Get a mutable slice to this object’s data.

impl TryFrom<Robj> for Function

fn try_from(robj: Robj) -> Result<Self>

Make a wrapper from a robj if it matches.

type Error = Error

The type returned in the event of a conversion error.

impl Types for Function

rtype() and rany()

fn rtype(&self) -> Rtype

Get the type of an R object.

fn as_any(&self) -> Rany<'_>

impl StructuralPartialEq for Function