riostream 0.1.3

A humorous attempt at implementing C++'s iostream and its syntax in Rust.
Documentation 
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
137
138
139
140
141
142

//! A humorous attempt at implementing C++'s iostream and its syntax in Rust.
//!
//! Differences from c++:
//!
//! * [`rin`] reads lines instead.
//! * [`endl`] and [`flush`] consumes the stream object to avoid an 'unused operator result' lint from rust.
//!
//! Disclaimer: this is purely for fun, do not use this crate in production.

use std::io::{stdin, stdout, Write, stderr};
use std::str::FromStr;
use std::fmt::Display;
use std::ops::{Shl, Shr};
use std::any::type_name;

/// Emulates the behavior of `cin`.
///
/// Unlike `cin`, this reads and parses a line.
///
/// # Examples
///
/// ```no_run
/// # use riostream::*;
/// let mut a = "".to_owned();
/// let mut b = 42;
/// rin >> &mut a >> &mut b;
/// ```
#[allow(nonstandard_style)]
pub struct rin;

/// Emulates the behavior of `cout`.
/// # Examples
///
/// ```
/// # use riostream::*;
/// rout << 42 << "Hello, World!!" << endl;
/// ```
#[allow(nonstandard_style)]
pub struct rout;

/// Emulates the behavior of `cerr`.
/// # Examples
///
/// ```
/// # use riostream::*;
/// rerr << 42 << "Hello, World!!" << endl;
/// ```
#[allow(nonstandard_style)]
pub struct rerr;

/// prints `'\n'` and flushes when passed to [`rout`] or [`rerr`]
///
/// This also consumes the stream to avoid an unused warning.
#[allow(nonstandard_style)]
pub struct endl;

/// Flushes when passed to [`rout`] or [`rerr`].
///
/// This also consumes the stream to avoid an unused warning.
#[allow(nonstandard_style)]
pub struct flush;

impl<T> Shl<T> for rout where T: Display{
    type Output = rout;

    fn shl(self, rhs: T) -> rout {
        stdout().write(rhs.to_string().as_bytes()).unwrap();
        self
    }
}

impl Shl<endl> for rout where{
    type Output = ();

    fn shl(self, _: endl) -> () {
        stdout().write(b"\n").unwrap();
        stdout().flush().unwrap();
    }
}

impl Shl<flush> for rout where{
    type Output = ();

    fn shl(self, _: flush) -> () {
        stdout().flush().unwrap();
    }
}


impl<T> Shl<T> for rerr where T: Display{
    type Output = rerr;

    fn shl(self, rhs: T) -> rerr {
        stderr().write(rhs.to_string().as_bytes()).unwrap();
        self
    }
}

impl Shl<endl> for rerr where{
    type Output = ();

    fn shl(self, _: endl) -> () {
        stderr().write(b"\n").unwrap();
        stderr().flush().unwrap();
    }
}

impl Shl<flush> for rerr where{
    type Output = ();

    fn shl(self, _: flush) -> () {
        stderr().flush().unwrap();
    }
}

impl<T> Shr<&mut T> for rin where T: FromStr {
    type Output = rin;

    #[allow(unused_results)]
    fn shr(self, rhs: &mut T) -> rin {
        let mut buf = String::new();
        stdin().read_line(&mut buf).unwrap();
        if let Ok(item) = T::from_str(&buf.trim()) {
            *rhs = item
        } else {
            panic!("\"{}\" is not a {}", &buf, type_name::<T>())
        };
        self
    }
}

impl Shr<flush> for rin {
    type Output = ();

    #[allow(unused_results)]
    fn shr(self, _: flush) -> () {}
}

#[test]
fn test() {
    rout << 1 << " " << "HelloWorld!" << endl;
}