Module glib::value [−][src]
Expand description
Value
binding and helper traits.
The type of a Value
is dynamic in that it generally
isn’t known at compile time but once created a Value
can’t change its
type.
SendValue
is a version of Value
that can only store types that implement Send
and as such implements Send
itself. It
dereferences to Value
so it can be used everywhere Value
references are accepted.
Supported types are bool
, i8
, u8
, i32
, u32
, i64
, u64
, f32
,
f64
, String
and objects (T: IsA<Object>
).
Examples
use glib::prelude::*; // or `use gtk::prelude::*;` use glib::Value; // Value implement From<&i32>, From<&str> and From<Option<&str>>. // Another option is the `ToValue` trait. let mut num = 10.to_value(); let mut hello = Value::from("Hello!"); let none: Option<&str> = None; let str_none = none.to_value(); // `is` tests the type of the value. assert!(num.is::<i32>()); assert!(hello.is::<String>()); // `get` tries to get an optional value of the specified type // and returns an `Err` if the type doesn't match. assert_eq!(num.get(), Ok(10)); assert!(num.get::<String>().is_err()); assert_eq!(hello.get(), Ok(String::from("Hello!"))); assert_eq!(hello.get::<String>(), Ok(String::from("Hello!"))); assert_eq!(str_none.get::<Option<String>>(), Ok(None));
Structs
BoxedValue | |
GenericValueTypeChecker | Generic |
GenericValueTypeOrNoneChecker | Generic |
SendValue | A version of |
Value | A generic value capable of carrying various types. |
ValueArray | |
ValueTypeMismatchError | An error returned from the |
Enums
ValueTypeMismatchOrNoneError | An error returned from the |
Traits
FromValue | Trait to retrieve the contained value from a |
FromValueOptional | Trait for types that implement |
ToSendValue | Converts to |
ToValue | Trait to convert a value to a |
ToValueOptional | Trait to convert an |
ValueType | A type that can be stored in |
ValueTypeChecker | Trait for |
ValueTypeOptional | A type that can be stored in |