dlang/treewalker/
repl.rs

1use std::io::{self, BufRead, Write};
2
3use crate::{
4    ast::Nodetrait,
5    heap::Heap,
6    lexer::Lexer,
7    object::{environment::Environment, ObjectTrait},
8    parser::Parser,
9    token::Kind,
10    treewalker::eval::evaluate,
11};
12const PROMPT: &str = "-> ";
13
14pub fn start() {
15    let mut buf = String::new();
16    let mut stdin = io::stdin().lock(); // We get `Stdin` here.
17
18    let mut env = Environment::new();
19    let mut heap = Heap::new();
20
21    let debug_lexer = false;
22    let debug_parser = false;
23    let debug_evaluator = false;
24    let show_error = true;
25
26    loop {
27        io::stdout().lock().write_all(PROMPT.as_bytes()).unwrap();
28        io::stdout().flush().unwrap();
29        match stdin.read_line(&mut buf) {
30            Ok(_) => {
31                if buf == "$env\n" {
32                    dbg!(&env);
33                    buf.clear();
34                    continue;
35                }
36                if buf == "$heap\n" {
37                    dbg!(&heap);
38                    buf.clear();
39                    continue;
40                }
41                if buf == "$rungc\n" {
42                    heap.run_gc(&mut env);
43                    buf.clear();
44                    continue;
45                }
46                let lexer = Lexer::new(buf.clone());
47
48                let mut cloned_lexer = lexer.clone();
49
50                if debug_lexer {
51                    loop {
52                        let cur_token = cloned_lexer.next_token();
53
54                        println!("Debug Output (Lexer) >> {:?}", cur_token);
55
56                        if cur_token.kind == Kind::EOF {
57                            break;
58                        }
59                    }
60                }
61
62                let mut parser = Parser::new(lexer);
63                let program = parser.parse();
64
65                if debug_parser {
66                    println!("Debug Output (Parser) >> {:?}", program);
67                }
68
69                if program.is_ok() {
70                    let program = program.unwrap();
71                    let result =
72                        evaluate(program.to_node(), &mut heap, &mut env);
73
74                    if debug_evaluator {
75                        println!("Debug Output (Eval) >> {:?}", result);
76                    }
77
78                    if result.is_ok() {
79                        let eval = result.unwrap();
80                        if eval.is_some() {
81                            let val = eval.unwrap();
82                            println!("{}", val.to_str());
83                        }
84                    } else if show_error {
85                        println!("!!!> ERROR OCCURED <!!!");
86                        println!(">> ERROR DETAIL ");
87                        println!("{:?}", result.err().unwrap());
88                    }
89                } else {
90                    if show_error {
91                        println!("!!!> ERROR OCCURED <!!!");
92                        for errs in program.err().unwrap() {
93                            println!(">> ERROR DETAIL ");
94                            for err in errs {
95                                println!("Pos>> {:?}", err.as_ref().position());
96                                println!("Detail>> {} ", err.as_ref().detail());
97                            }
98                        }
99                    }
100                }
101                buf.clear();
102            }
103            Err(err) => {
104                println!("Error occured during reading stdin");
105                println!("{:?}", err);
106                return;
107            }
108        }
109    }
110}
dlang/treewalker/repl.rs

dlang/treewalker/
repl.rs
