Trait rutie::TryConvert

pub trait TryConvert<T>: Sized {
    type Nil;
    fn try_convert(value: T) -> Result<Self, Self::Nil>;
}

Implicit conversion or nil.

This is meant for “implicit conversions” much like Ruby’s:

• Array.try_convert
• Hash.try_convert
• String.try_convert
• Regexp.try_convert
• IO.try_convert

This is NOT Rust object to Rust object casting for Ruby objects like try_convert_to<T> is.

Associated Types

type Nil

The type returned in the event of a conversion error.

Required methods

fn try_convert(value: T) -> Result<Self, Self::Nil>

Performs the conversion.

Implementors

impl TryConvert<AnyObject> for AnyException

type Nil = NilClass

impl TryConvert<AnyObject> for RString

Implicit or nil conversion

Examples

use rutie::{RString, Fixnum, VM, TryConvert, NilClass, Object};

let four = Fixnum::new(4);
let result = RString::try_convert(four.to_any_object());

assert_eq!(result, Err(NilClass::new()));

let five = RString::new_utf8("5");
let result2 = RString::try_convert(five.to_any_object());

if let Ok(r) = result2 {
  assert_eq!(r.to_str(), "5")
} else {
  unreachable!()
}

Ruby:

four = 4
result = String.try_convert(four)

result == nil

five = "5"
result = String.try_convert(five)

result == "5"

type Nil = NilClass