Improve input

libs/input/src/lib.rs

@@ -1,27 +1,76 @@
-/// Provids utility on stdin.
+//! Read input from stdin and parse it.
+//!
+//! # Example
+//!
+//! ```[no_run]
+//! # use input::input;
+//! let (a, b): (i32, i32) = input();
+//! let a: Vec<i32> = input();
+//! ```
+//!
+//! # Types that can be parsed
+//! - primitive integer types ([`u8`], [`u16`], [`u32`], [`u64`], [`u128`], [`usize`], [`i8`], [`i16`], [`i32`], [`i64`], [`i128`], [`isize`])
+//! - [`String`], [`char`]
+//! - tuples (up to 10 elements)
+//! - vectors
+
 use std::cell::Cell;
-/// Provids utility on stdin.
-use std::convert::TryFrom;
-/// Provids utility on stdin.
 use std::io::stdin;
-/// Provids utility on stdin.
 use std::io::BufRead;
-/// Provids utility on stdin.
 use std::io::BufReader;
-/// Provids utility on stdin.
 use std::io::Lines;
-/// Provids utility on stdin.
 use std::io::Stdin;
-/// Provids utility on stdin.
-use std::str::FromStr;
-/// Provids utility on stdin.
 use std::sync::Mutex;
-/// Provids utility on stdin.
 use std::sync::Once;
 
-type Server = Mutex<Lines<BufReader<Stdin>>>;
+/// Read input from stdin and parse it.
+pub fn input<T: ParseLine>() -> T {
+    ParseLine::parse_line(&line())
+}
+
+/// Trait for types that can be parsed.
+pub trait ParseLine {
+    fn parse_line(s: &str) -> Self;
+}
+
+macro_rules! impl_parse_line {
+    ($($t:ty),*) => {
+        $(impl ParseLine for $t {
+            fn parse_line(s: &str) -> Self {
+                s.parse().unwrap()
+            }
+        })*
+    };
+}
+impl_parse_line!(u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize, String, char);
+macro_rules! impl_parse_line_tuple {
+    ($($t:ident),*) => {
+        impl<$($t: ParseLine),*> ParseLine for ($($t,)*) {
+            fn parse_line(s: &str) -> Self {
+                let mut s = s.split_whitespace();
+                ($($t::parse_line(s.next().unwrap()),)*)
+            }
+        }
+    };
+}
+impl_parse_line_tuple!(T0, T1);
+impl_parse_line_tuple!(T0, T1, T2);
+impl_parse_line_tuple!(T0, T1, T2, T3);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4, T5);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4, T5, T6);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4, T5, T6, T7);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4, T5, T6, T7, T8);
+impl_parse_line_tuple!(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9);
+impl<T: ParseLine> ParseLine for Vec<T> {
+    fn parse_line(s: &str) -> Self {
+        s.split_whitespace().map(T::parse_line).collect()
+    }
+}
+
 static ONCE: Once = Once::new();
-pub struct Lazy(Cell<Option<Server>>);
+type Server = Mutex<Lines<BufReader<Stdin>>>;
+struct Lazy(Cell<Option<Server>>);
 unsafe impl Sync for Lazy {}
 fn line() -> String {
     static SYNCER: Lazy = Lazy(Cell::new(None));
@@ -41,29 +90,3 @@ fn line() -> String {
             .unwrap()
     }
 }
-pub trait ForceFromStr: FromStr {
-    fn force_from_str(s: &str) -> Self;
-}
-impl<T, E> ForceFromStr for T
-where
-    T: FromStr<Err = E>,
-    E: std::fmt::Debug,
-{
-    fn force_from_str(s: &str) -> Self { s.parse().unwrap() }
-}
-/// Read a line from stdin and from_str to [T; N].
-pub fn input_array<T: ForceFromStr, const N: usize>() -> [T; N]
-where
-    T: std::fmt::Debug,
-{
-    <[_; N]>::try_from(input_vec()).unwrap()
-}
-/// Read a line from stdin and from_str to [`Vec<T>`].
-pub fn input_vec<T: ForceFromStr>() -> Vec<T> {
-    line()
-        .split_whitespace()
-        .map(T::force_from_str)
-        .collect::<Vec<_>>()
-}
-/// Read a line from stdin and from_str to T.
-pub fn input<T: ForceFromStr>() -> T { T::force_from_str(&line()) }