ripex 0.3.0

Multi-language structural parsing and fact extraction.
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

use crate::js::lexer::scanner::Scanner;
use crate::js::lexer::token::TokenKind;

pub fn scan_string(scanner: &mut Scanner, quote: char) -> String {
    let mut result = String::new();
    loop {
        match scanner.advance() {
            None | Some('\n') | Some('\r') => {
                return result;
            }
            Some(ch) if ch == quote => {
                return result;
            }
            Some('\\') => {
                if let Some(c) = scan_escape(scanner) {
                    result.push(c);
                }
            }
            Some(ch) => {
                result.push(ch);
            }
        }
    }
}

pub fn scan_template(scanner: &mut Scanner) -> (String, TokenKind) {
    let mut result = String::new();
    loop {
        match scanner.peek() {
            None => {
                return (result, TokenKind::TemplateTail);
            }
            Some('`') => {
                scanner.advance();
                return (result, TokenKind::TemplateTail);
            }
            Some('$') if scanner.peek_ahead(1) == Some('{') => {
                scanner.advance();
                scanner.advance();
                return (result, TokenKind::TemplateHead);
            }
            Some('\\') => {
                scanner.advance();
                if let Some(c) = scan_escape(scanner) {
                    result.push(c);
                }
            }
            Some(ch) => {
                scanner.advance();
                result.push(ch);
            }
        }
    }
}

fn scan_escape(scanner: &mut Scanner) -> Option<char> {
    Some(match scanner.advance()? {
        'n' => '\n',
        't' => '\t',
        'r' => '\r',
        'b' => '\u{0008}',
        'f' => '\u{000C}',
        'v' => '\u{000B}',
        '\\' => '\\',
        '\'' => '\'',
        '"' => '"',
        '`' => '`',
        '0' => {
            if matches!(scanner.peek(), Some('0'..='7')) {
                let mut code = 0u32;
                for _ in 0..3 {
                    match scanner.peek() {
                        Some(d @ '0'..='7') => {
                            scanner.advance();
                            code = code * 8 + (d as u32 - '0' as u32);
                        }
                        _ => break,
                    }
                }
                char::from_u32(code).unwrap_or('\u{FFFD}')
            } else {
                '\0'
            }
        }
        'x' => {
            let hi = scanner.advance().and_then(hex_val);
            let lo = scanner.advance().and_then(hex_val);
            match (hi, lo) {
                (Some(h), Some(l)) => ((h << 4) | l) as char,
                _ => '\u{FFFD}',
            }
        }
        'u' => {
            if scanner.peek() == Some('{') {
                scanner.advance();
                let mut code = 0u32;
                loop {
                    match scanner.peek() {
                        Some('}') => {
                            scanner.advance();
                            break;
                        }
                        Some(d) if d.is_ascii_hexdigit() => {
                            scanner.advance();
                            code = code * 16 + d.to_digit(16).unwrap();
                        }
                        _ => break,
                    }
                }
                char::from_u32(code).unwrap_or('\u{FFFD}')
            } else {
                let hi = scanner.advance().and_then(hex_val);
                let lo = scanner.advance().and_then(hex_val);
                match (hi, lo) {
                    (Some(h), Some(l)) => ((h << 4) | l) as char,
                    _ => '\u{FFFD}',
                }
            }
        }
        '\r' => {
            if scanner.peek() == Some('\n') {
                scanner.advance();
            }
            return None;
        }
        '\n' => {
            return None;
        }
        ch => ch,
    })
}

fn hex_val(c: char) -> Option<u8> {
    match c {
        '0'..='9' => Some(c as u8 - b'0'),
        'a'..='f' => Some(c as u8 - b'a' + 10),
        'A'..='F' => Some(c as u8 - b'A' + 10),
        _ => None,
    }
}