1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
// #![deny(missing_docs, missing_debug_implementations)]

//! Returns type names with a specifiable number of module segments as a `String`.
//!
//! ```rust
//! // === std library === //
//! assert_eq!(
//!     std::any::type_name::<Option<String>>(),
//!     "core::option::Option<alloc::string::String>",
//! );
//!
//! // === tynm === //
//! // Simple type name:
//! assert_eq!(tynm::type_name::<Option<String>>(), "Option<String>",);
//!
//! // Type name with 1 module segment, starting from the most significant module.
//! assert_eq!(
//!     tynm::type_namem::<Option<String>>(1),
//!     "core::..::Option<alloc::..::String>",
//! );
//!
//! // Type name with 1 module segment, starting from the least significant module.
//! assert_eq!(
//!     tynm::type_namen::<Option<String>>(1),
//!     "..::option::Option<..::string::String>",
//! );
//!
//! // Type name with 1 module segment from both the most and least significant modules.
//! #[rustfmt::skip]
//! mod rust_out { pub mod two { pub mod three { pub struct Struct; } } }
//! assert_eq!(
//!     tynm::type_namemn::<rust_out::two::three::Struct>(1, 1),
//!     "rust_out::..::three::Struct",
//! );
//! ```
//!
//! # Motivation
//!
//! The [`std::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.
//!
//! [`std::any::type_name`]: https://doc.rust-lang.org/std/any/fn.type_name.html

pub use crate::types::TypeName;

mod parser;
mod types;

/// Returns the simple type name.
///
/// # Type Parameters
///
/// * `T`: Type whose simple type name should be returned.
///
/// # Examples
///
/// ```rust
/// assert_eq!(tynm::type_name::<Option<String>>(), "Option<String>",);
/// ```
pub fn type_name<T>() -> String {
    type_namemn::<T>(0, 0)
}

/// Returns the type name with at most `m` most significant module path segments.
///
/// # Parameters
///
/// * `m`: Number of most significant module path segments to include.
///
/// # Type Parameters
///
/// * `T`: Type whose simple type name should be returned.
///
/// # Examples
///
/// ```rust
/// assert_eq!(
///     tynm::type_namem::<Option<String>>(1),
///     "core::..::Option<alloc::..::String>",
/// );
/// ```
pub fn type_namem<T>(m: usize) -> String {
    type_namemn::<T>(m, 0)
}

/// Returns the type name with at most `n` least significant module path segments.
///
/// # Parameters
///
/// * `n`: Number of least significant module path segments to include.
///
/// # Type Parameters
///
/// * `T`: Type whose simple type name should be returned.
///
/// # Examples
///
/// ```rust
/// assert_eq!(
///     tynm::type_namen::<Option<String>>(1),
///     "..::option::Option<..::string::String>",
/// );
/// ```
pub fn type_namen<T>(n: usize) -> String {
    type_namemn::<T>(0, n)
}

/// Returns the type name with `m` most significant, and `n` least significant module path segments.
///
/// # Parameters
///
/// * `m`: Number of most significant module path segments to include.
/// * `n`: Number of least significant module path segments to include.
///
/// # Type Parameters
///
/// * `T`: Type whose simple type name should be returned.
///
/// # Examples
///
/// ```rust
/// assert_eq!(
///     tynm::type_namen::<Option<String>>(1),
///     "..::option::Option<..::string::String>",
/// );
/// ```
pub fn type_namemn<T>(m: usize, n: usize) -> String {
    let type_name_qualified = std::any::type_name::<T>();

    let type_name = TypeName::from(type_name_qualified);
    type_name.as_str_mn(m, n)
}