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History

mokou ed0f278a8f chore: remove mod.rs files and exercises feature		2022-07-11 12:53:49 +02:00
..
as_ref_mut.rs	chore: Alter whitespace for consistency	2020-07-11 11:50:54 -07:00
from_into.rs	feat(from_into) : add test for checking unnecessary trailing value	2021-01-09 00:08:38 +09:00
from_str.rs	Merge pull request #781 from tlyu/advanced-errs	2021-09-25 11:18:55 +02:00
README.md	docs(exercises): updated all exercises readme files	2021-04-23 19:54:31 +02:00
try_from_into.rs	fix(from_str, try_from_into): custom error types	2021-06-24 21:33:41 -05:00
using_as.rs	refactor(using_as): improve readability by using sum() instead of fold()	2022-04-19 17:37:00 +02:00

README.md

Type conversions

Rust offers a multitude of ways to convert a value of a given type into another type.

The simplest form of type conversion is a type cast expression. It is denoted with the binary operator as. For instance, println!("{}", 1 + 1.0); would not compile, since 1 is an integer while 1.0 is a float. However, println!("{}", 1 as f32 + 1.0) should compile. The exercise using_as tries to cover this.

Rust also offers traits that facilitate type conversions upon implementation. These traits can be found under the convert module. The traits are the following:

From and Into covered in from_into
TryFrom and TryInto covered in try_from_into
AsRef and AsMut covered in as_ref_mut

Furthermore, the std::str module offers a trait called FromStr which helps with converting strings into target types via the parse method on strings. If properly implemented for a given type Person, then let p: Person = "Mark,20".parse().unwrap() should both compile and run without panicking.

These should be the main ways within the standard library to convert data into your desired types.

Further information

These are not directly covered in the book, but the standard library has a great documentation for it.