Struct magnus::class::RClass

#[repr(transparent)]
pub struct RClass(_);

A Value pointer to a RClass struct, Ruby’s internal representation of classes.

See the Module trait for defining instance methods and nested classes/modules. See the Object trait for defining singlton methods (aka class methods).

All Value methods should be available on this type through Deref, but some may be missed by this documentation.

Implementations

impl RClass

pub fn from_value(val: Value) -> Option<Self>

Return Some(RClass) if val is a RClass, None otherwise.

Examples

use magnus::{eval, RClass};

assert!(RClass::from_value(eval("String").unwrap()).is_some());
assert!(RClass::from_value(eval("Enumerable").unwrap()).is_none());
assert!(RClass::from_value(eval("nil").unwrap()).is_none());

pub fn new(superclass: RClass) -> Result<RClass, Error>

Create a new anonymous class.

Examples

use magnus::{class, RClass};

let class = RClass::new(Default::default()).unwrap();
assert!(class.is_kind_of(class::class()));

pub fn new_instance<T>(self, args: T) -> Result<Value, Error>where
    T: ArgList,

Create a new object, an instance of self, passing the arguments args to the initialiser.

Examples

use magnus::class;

let s = class::string().new_instance(()).unwrap();
assert!(s.is_kind_of(class::string()));
assert_eq!(s.to_string(), "");

pub fn superclass(self) -> Result<Self, Error>

Returns the parent class of self.

Returns Err if self can not have a parent class.

Examples

use magnus::{class, eval};

let klass = class::hash().superclass().unwrap();
assert!(klass.equal(class::object()).unwrap());

pub unsafe fn name(&self) -> Cow<'_, str>

Return the name of self.

Safety

Ruby may modify or free the memory backing the returned str, the caller must ensure this does not happen.

This can be used safely by immediately calling into_owned on the return value.

Examples

use magnus::{class, eval};

let value = class::hash();
// safe as we neve give Ruby a chance to free the string.
let s = unsafe { value.name() }.into_owned();
assert_eq!(s, "Hash");

Methods from Deref<Target = Value>

pub unsafe fn to_s(&self) -> Result<Cow<'_, str>, Error>

Convert self to a Rust string.

Safety

This may return a direct view of memory owned and managed by Ruby. Ruby may modify or free the memory backing the returned str, the caller must ensure this does not happen.

This can be used safely by immediately calling into_owned on the return value.

Examples

use magnus::{eval, QTRUE};

let value = QTRUE;
// safe as we neve give Ruby a chance to free the string.
let s = unsafe { value.to_s() }.unwrap().into_owned();
assert_eq!(s, "true");

pub unsafe fn classname(&self) -> Cow<'_, str>

Return the name of self’s class.

Safety

Ruby may modify or free the memory backing the returned str, the caller must ensure this does not happen.

This can be used safely by immediately calling into_owned on the return value.

Examples

use magnus::{eval, RHash};

let value = RHash::new();
// safe as we never give Ruby a chance to free the string.
let s = unsafe { value.classname() }.into_owned();
assert_eq!(s, "Hash");

Trait Implementations

impl Class for RClass

type Instance = Value

The type representing an instance of the class Self.

fn new(superclass: Self) -> Result<Self, Error>

Create a new anonymous class.

fn new_instance<T>(self, args: T) -> Result<Self::Instance, Error>where
    T: ArgList,

Create a new object, an instance of self, passing the arguments args to the initialiser.

fn superclass(self) -> Result<RClass, Error>

Returns the parent class of self.

unsafe fn name(&self) -> Cow<'_, str>

Return the name of self.

fn as_r_class(self) -> RClass

Return self as an RClass.

impl Clone for RClass

fn clone(&self) -> RClass

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for RClass

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

Formats the value using the given formatter.

impl Default for RClass

fn default() -> Self

Returns the “default value” for a type.

impl Deref for RClass

type Target = Value

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Display for RClass

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

Formats the value using the given formatter.

impl From<RClass> for Value

fn from(val: RClass) -> Self

Converts to this type from the input type.

impl Module for RClass

fn define_class<T: Into<Id>>(
    self,
    name: T,
    superclass: RClass
) -> Result<RClass, Error>

Define a class in self’s scope.

fn define_module<T: Into<Id>>(self, name: T) -> Result<RModule, Error>

Define a module in self’s scope.

fn define_error<T: Into<Id>>(
    self,
    name: T,
    superclass: ExceptionClass
) -> Result<ExceptionClass, Error>

Define an exception class in self’s scope.

fn include_module(self, module: RModule) -> Result<(), Error>

Include module into self.

fn prepend_module(self, module: RModule) -> Result<(), Error>

Prepend self with module.

fn const_set<T, U>(self, name: T, value: U) -> Result<(), Error>where
    T: Into<Id>,
    U: Into<Value>,

Set the value for the constant name within self’s scope.

fn const_get<T, U>(self, name: T) -> Result<U, Error>where
    T: Into<Id>,
    U: TryConvert,

Get the value for the constant name within self’s scope.

fn is_inherited<T>(self, other: T) -> boolwhere
    T: Deref<Target = Value> + Module,

Returns whether or not self inherits from other.

fn ancestors(self) -> RArray

Return the classes and modules self inherits, includes, or prepends.

fn define_method<T, M>(self, name: T, func: M) -> Result<(), Error>where
    T: Into<Id>,
    M: Method,

Define a method in self’s scope.

fn define_private_method<M>(self, name: &str, func: M) -> Result<(), Error>where
    M: Method,

Define a private method in self’s scope.

fn define_protected_method<M>(self, name: &str, func: M) -> Result<(), Error>where
    M: Method,

Define a protected method in self’s scope.

fn define_attr<T>(self, name: T, rw: Attr) -> Result<(), Error>where
    T: Into<Id>,

Define public accessor methods for the attribute name.

fn define_alias<T, U>(self, dst: T, src: U) -> Result<(), Error>where
    T: Into<Id>,
    U: Into<Id>,

Alias the method src of self as dst.

impl Object for RClass

fn define_singleton_method<M>(self, name: &str, func: M) -> Result<(), Error>where
    M: Method,

Define a singleton method in self’s scope.

fn ivar_get<T, U>(self, name: T) -> Result<U, Error>where
    T: Into<Id>,
    U: TryConvert,

Get the value for the instance variable name within self’s scope.

fn ivar_set<T, U>(self, name: T, value: U) -> Result<(), Error>where
    T: Into<Id>,
    U: Into<Value>,

Set the value for the instance variable name within self’s scope.

fn singleton_class(self) -> Result<RClass, Error>

Finds or creates the singleton class of self.

fn extend_object(self, module: RModule) -> Result<(), Error>

Extend self with module.

impl TryConvert for RClass

fn try_convert(val: Value) -> Result<Self, Error>

Convert val into Self.

impl Copy for RClass

impl ReprValue for RClass