luars 0.26.2

A library for lua 5.5 runtime implementation 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

mod lua_language_level;
mod lua_operator_kind;
mod lua_token_data;
mod lua_token_kind;
mod lua_tokenize;
mod reader;
mod text_range;
mod tokenize_config;

pub use crate::compiler::parser::{
    lua_language_level::LuaLanguageLevel, lua_operator_kind::*, lua_token_data::LuaTokenData,
    lua_token_kind::LuaTokenKind, lua_tokenize::LuaTokenize, reader::Reader,
    text_range::SourceRange, tokenize_config::TokensizeConfig,
};

pub struct LuaLexer<'a> {
    text: &'a str,
    tokenizer: LuaTokenize<'a>,
    current: LuaTokenData,
    next: LuaTokenData,
    previous: Option<SourceRange>,
    token_index: usize,
    current_token: LuaTokenKind,
    error: Option<String>,
    #[allow(unused)]
    pub level: LuaLanguageLevel,
    pub line: usize,          // current line number (linenumber in Lua)
    pub lastline: usize,      // line of last token consumed (lastline in Lua)
    pub nesting_level: usize, // parser nesting depth (like C Lua's nCcalls during compilation)
}

#[allow(unused)]
impl<'a> LuaLexer<'a> {
    pub fn new(text: &'a str, level: LuaLanguageLevel) -> Result<LuaLexer<'a>, String> {
        let mut tokenizer = LuaTokenize::new(
            Reader::new(text),
            TokensizeConfig {
                language_level: level,
            },
        );

        let current = tokenizer.next_token_data()?;
        let next = tokenizer.next_token_data()?;

        Ok(LuaLexer {
            text,
            tokenizer,
            current_token: current.kind,
            current,
            next,
            previous: None,
            token_index: 0,
            error: None,
            level,
            line: current.line,
            lastline: 1,
            nesting_level: 0,
        })
    }

    pub fn origin_text(&self) -> &'a str {
        self.text
    }

    pub fn current_token(&self) -> LuaTokenKind {
        self.current_token
    }

    pub fn current_token_index(&self) -> usize {
        self.token_index
    }

    pub fn current_token_range(&self) -> SourceRange {
        self.current.range
    }

    pub fn previous_token_range(&self) -> SourceRange {
        self.previous.unwrap_or(SourceRange::EMPTY)
    }

    pub fn current_token_text(&self) -> &str {
        if self.current_token == LuaTokenKind::TkEof {
            return "<eof>";
        }
        let range = &self.current.range;
        &self.text[range.start_offset..range.end_offset()]
    }

    pub fn set_current_token_kind(&mut self, kind: LuaTokenKind) {
        self.current.kind = kind;
        self.current_token = kind;
    }

    pub fn bump(&mut self) {
        // Port of luaX_next from llex.c:565-573
        // Save current line before consuming next token
        self.lastline = self.line;

        self.previous = Some(self.current.range);
        self.current = self.next;
        self.current_token = self.current.kind;
        self.line = self.current.line;
        self.token_index += 1;

        if self.current.kind == LuaTokenKind::TkEof {
            self.current_token = LuaTokenKind::TkEof;
            return;
        }

        match self.tokenizer.next_token_data() {
            Ok(token) => self.next = token,
            Err(err) => {
                self.error = Some(err);
                self.next =
                    LuaTokenData::with_line(LuaTokenKind::TkEof, self.current.range, self.line);
                self.current = self.next;
                self.current_token = LuaTokenKind::TkEof;
            }
        }
    }

    pub fn peek_next_token(&self) -> LuaTokenKind {
        self.next.kind
    }

    pub fn take_error(&mut self) -> Option<String> {
        self.error.take()
    }
}