fret_runtime/when_expr/
mod.rs

1mod ast;
2mod eval;
3mod parser;
4mod validate;
5
6#[cfg(test)]
7mod tests;
8
9use std::sync::Arc;
10
11use crate::InputContext;
12
13use ast::Expr;
14
15#[derive(Debug, Clone, PartialEq, Eq, Hash)]
16pub struct WhenExpr(Expr);
17
18/// Evaluation context for `when` expressions.
19///
20/// This is intentionally a small, data-only view that can be extended without forcing new
21/// `InputContext` fields (which would require widespread struct literal churn).
22#[derive(Debug, Clone, Copy)]
23pub struct WhenEvalContext<'a> {
24    pub input: &'a InputContext,
25    pub key_contexts: &'a [Arc<str>],
26}
27
28impl<'a> WhenEvalContext<'a> {
29    pub fn new(input: &'a InputContext) -> Self {
30        Self {
31            input,
32            key_contexts: &[],
33        }
34    }
35
36    pub fn with_key_contexts(input: &'a InputContext, key_contexts: &'a [Arc<str>]) -> Self {
37        Self {
38            input,
39            key_contexts,
40        }
41    }
42}
43
44impl WhenExpr {
45    pub fn parse(input: &str) -> Result<Self, String> {
46        Ok(Self(parser::parse(input)?))
47    }
48
49    pub fn validate(&self) -> Result<(), WhenExprValidationError> {
50        self.0.validate_bool_expr()
51    }
52
53    pub fn eval(&self, ctx: &InputContext) -> bool {
54        self.eval_in(&WhenEvalContext::new(ctx))
55    }
56
57    pub fn eval_with_key_contexts(&self, ctx: &InputContext, key_contexts: &[Arc<str>]) -> bool {
58        self.eval_in(&WhenEvalContext::with_key_contexts(ctx, key_contexts))
59    }
60
61    pub fn eval_in(&self, cx: &WhenEvalContext<'_>) -> bool {
62        self.0.eval(cx)
63    }
64}
65
66pub use validate::{WhenExprValidationError, WhenValueKind};
fret_runtime/when_expr/mod.rs

fret_runtime/when_expr/
mod.rs
