tour_core/
syntax.rs

1
2/// An expression delimiter.
3//
4// Opening and closing delimiter must be equal.
5#[derive(Clone, Copy, PartialEq, Eq)]
6pub enum Delimiter {
7    /// `{{ }}` escaped render.
8    Brace,
9    /// `{! !}` unescaped render.
10    Bang,
11    /// `{% %}` escaped render using `std::fmt::Display`.
12    Percent,
13    /// `{? ?}` escaped render using `std::fmt::Debug`.
14    Quest,
15    /// `{# #}` unused, same as [`Delimiter::Brace`].
16    Hash,
17    // /// `{@ @}`
18    // At,
19    // /// `{$ $}`
20    // Dollar,
21    // /// `{^ ^}`
22    // Caret,
23    // /// `{& &}`
24    // And,
25    // /// `{* *}`
26    // Star,
27    // /// `{( )}`
28    // Paren,
29    // /// `{[ ]}`
30    // Bracket,
31}
32
33impl Delimiter {
34    /// Returns [`Some`] if given byte considered as opening delimiter.
35    pub fn match_open(ch: u8) -> Option<Self> {
36        match ch {
37            b'{' => Some(Self::Brace),
38            b'!' => Some(Self::Bang),
39            b'%' => Some(Self::Percent),
40            b'?' => Some(Self::Quest),
41            b'#' => Some(Self::Hash),
42            _ => None,
43        }
44    }
45
46    /// Returns [`Some`] if given byte considered as closing delimiter.
47    pub fn match_close(ch: u8) -> Option<Self> {
48        match ch {
49            b'}' => Some(Self::Brace),
50            b'!' => Some(Self::Bang),
51            b'%' => Some(Self::Percent),
52            b'?' => Some(Self::Quest),
53            b'#' => Some(Self::Hash),
54            _ => None,
55        }
56    }
57}
58
59impl std::fmt::Display for Delimiter {
60    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
61        match self {
62            Self::Brace => f.write_str("brace"),
63            Self::Bang => f.write_str("!"),
64            Self::Percent => f.write_str("%"),
65            Self::Quest => f.write_str("?"),
66            Self::Hash => f.write_str("#"),
67        }
68    }
69}
70
tour_core/syntax.rs

tour_core/
syntax.rs
