locrian 0.2.2

A simple embeddable functional programming language.
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

use std::io::{self, Write};

use lazy_static::lazy_static;

use crate::{
    eval::{EvalContext, EvalResult},
    parser::{ExprValue, parse_expr},
};

pub(crate) fn write_unescaped(args: Vec<EvalResult>) -> EvalResult {
    if let Some(EvalResult::String(s)) = args.get(0) {
        io::stdout().write_all(s.as_bytes()).unwrap();
        io::stdout().flush().unwrap();
    } else {
        println!("{:?}", args.get(0));
    }
    EvalResult::None
}

pub(crate) static write: &str = r#"
    io:write_unescaped(string:escape(string:concat(...$arguments)))
    "#;

pub(crate) static writeln: &str = r#"
    use(["io", "array"], 'write(...append($arguments, lf)))
    "#;

pub(crate) static format: &str = r#"
    use(["io"], 'write(string:format(...$arguments)))
    "#;

lazy_static! {
    pub static ref IO: EvalContext<'static> = EvalContext::new()
        .with_fn("io:write_unescaped", write_unescaped)
        .with_var(
            "io:write",
            ExprValue::Quote(Box::new(parse_expr(write).unwrap()))
        )
        .with_var(
            "io:writeln",
            ExprValue::Quote(Box::new(parse_expr(writeln).unwrap()))
        )
        .with_var(
            "io:format",
            ExprValue::Quote(Box::new(parse_expr(format).unwrap()))
        );
}

#[cfg(test)]
mod tests {
    use crate::{eval_str, io::IO, stdlib::STDLIB};

    #[test]
    fn test_write_unescaped() {
        eval_str(
            r#"io:write_unescaped("Hello world")"#,
            STDLIB.merge(IO.clone()),
        )
        .unwrap();
    }

    #[test]
    fn test_write() {
        eval_str(r#"io:write("Hello world")"#, STDLIB.merge(IO.clone())).unwrap();
    }

    #[test]
    fn test_writeln() {
        eval_str(r#"io:writeln("Hello world")"#, STDLIB.merge(IO.clone())).unwrap();
    }

    #[test]
    fn test_format() {
        eval_str(
            r#"io:format("Hello {}~n", "world")"#,
            STDLIB.merge(IO.clone()),
        )
        .unwrap();
    }
}