carta_core/template/
node.rs

1//! The parsed template tree and its expression nodes.
2
3/// A parsed template: a flat sequence of nodes, with `$if$`/`$for$` holding their bodies inline.
4#[derive(Debug, Clone, PartialEq)]
5pub struct Template {
6    pub(crate) nodes: Vec<Node>,
7}
8
9/// One element of a rendered template.
10#[derive(Debug, Clone, PartialEq)]
11pub(crate) enum Node {
12    /// Verbatim text between directives.
13    Literal(String),
14    /// A variable interpolation, e.g. `$title$` or `$x.y/uppercase$`.
15    Var(Expr),
16    /// `$if(..)$ .. $elseif(..)$ .. $else$ .. $endif$`: ordered guarded branches plus an else body.
17    If {
18        branches: Vec<(Expr, Vec<Node>)>,
19        otherwise: Vec<Node>,
20    },
21    /// `$for(..)$ body $sep$ separator $endfor$`.
22    For {
23        expr: Expr,
24        /// The single bound name when the loop expression is one bare segment, for `$name$` access
25        /// inside the body (`$it$` always works regardless).
26        bind: Option<String>,
27        body: Vec<Node>,
28        sep: Vec<Node>,
29    },
30    /// `$name()$`, or mapped `$xs:name()$` / `$xs:name()[sep]$`.
31    Partial {
32        name: String,
33        map_over: Option<Expr>,
34        sep: Option<String>,
35    },
36}
37
38/// A variable reference: a dotted lookup path plus a chain of pipes applied to the result.
39#[derive(Debug, Clone, PartialEq)]
40pub(crate) struct Expr {
41    pub(crate) path: Vec<String>,
42    pub(crate) pipes: Vec<Pipe>,
43}
44
45/// A single filter applied to a value.
46#[derive(Debug, Clone, PartialEq)]
47pub(crate) enum Pipe {
48    Uppercase,
49    Lowercase,
50    Length,
51    Reverse,
52    First,
53    Last,
54    Rest,
55    AllButLast,
56    Pairs,
57    Alpha,
58    Roman,
59    Chomp,
60    Nowrap,
61    /// Pad a value into a fixed-width block, optionally framed by border strings.
62    Block {
63        align: Align,
64        width: usize,
65        left: String,
66        right: String,
67    },
68}
69
70/// Alignment for the [`Pipe::Block`] padding filters.
71#[derive(Debug, Clone, Copy, PartialEq, Eq)]
72pub(crate) enum Align {
73    Left,
74    Right,
75    Center,
76}
carta_core/template/node.rs

carta_core/template/
node.rs
