🪶 Tynm -- Type Name

Returns type names with a specifiable number of module segments as a String.

Usage

Add the following to Cargo.toml

tynm = "0.2.0"

In code:

#[rustfmt::skip]
assert_eq!(
    core::any::type_name::<Option<String>>(), "core::option::Option<alloc::string::String>"
);

#[rustfmt::skip]
let tuples = vec![
    (tynm::type_name::<Option<String>>(),    "Option<String>"),
    (tynm::type_namem::<Option<String>>(1),  "core::..::Option<alloc::..::String>"),
    (tynm::type_namen::<Option<String>>(1),  "..::option::Option<..::string::String>"),
    // 1 segment from most and least significant modules.
    (tynm::type_namemn::<rust_out::two::three::Struct>(1, 1), "rust_out::..::three::Struct"),
    // traits
    (tynm::type_name::<dyn core::fmt::Debug>(), "dyn Debug"),
];

tuples
    .iter()
    .for_each(|(left, right)| assert_eq!(left, right));

Motivation

The core::any::type_name function stabilized in Rust 1.38 returns the fully qualified type name with all module segments. This can be difficult to read in error messages, especially for type-parameterized types.

Often, the simple type name is more readable, and enough to distinguish the type referenced in an error.

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.