toasty_core/stmt/
expr_and.rs

1use super::Expr;
2
3use std::ops;
4
5/// A logical "and" of multiple expressions.
6///
7/// Returns `true` only if all operands evaluate to `true`. An `ExprAnd` always
8/// has at least two operands; use [`Expr::and_from_vec`] which returns
9/// `Expr::Value(true)` for empty input and unwraps single-element input.
10///
11/// # Examples
12///
13/// ```text
14/// and(a, b, c)  // returns `true` if `a`, `b`, and `c` are all `true`
15/// ```
16#[derive(Debug, Clone, PartialEq)]
17pub struct ExprAnd {
18    /// The expressions to "and" together.
19    pub operands: Vec<Expr>,
20}
21
22impl Expr {
23    /// Creates an AND expression from two operands.
24    ///
25    /// Flattens nested ANDs: `and(and(a, b), c)` produces `and(a, b, c)`.
26    /// Short-circuits on `true`: `and(true, x)` returns `x`.
27    pub fn and(lhs: impl Into<Self>, rhs: impl Into<Self>) -> Self {
28        let mut lhs = lhs.into();
29        let rhs = rhs.into();
30
31        match (&mut lhs, rhs) {
32            (expr, rhs) if expr.is_true() => rhs,
33            (_, expr) if expr.is_true() => lhs,
34            (Self::And(lhs_and), Self::And(rhs_and)) => {
35                lhs_and.operands.extend(rhs_and.operands);
36                lhs
37            }
38            (Self::And(lhs_and), rhs) => {
39                lhs_and.operands.push(rhs);
40                lhs
41            }
42            (_, Self::And(mut rhs_and)) => {
43                rhs_and.operands.push(lhs);
44                rhs_and.into()
45            }
46            (_, rhs) => ExprAnd {
47                operands: vec![lhs, rhs],
48            }
49            .into(),
50        }
51    }
52
53    /// Creates an AND expression from a vector of operands.
54    ///
55    /// Returns `Expr::Value(true)` for an empty vector and unwraps
56    /// single-element vectors into the element itself.
57    pub fn and_from_vec(operands: Vec<Self>) -> Self {
58        if operands.is_empty() {
59            return true.into();
60        }
61
62        if operands.len() == 1 {
63            return operands.into_iter().next().unwrap();
64        }
65
66        ExprAnd { operands }.into()
67    }
68}
69
70impl ops::Deref for ExprAnd {
71    type Target = [Expr];
72
73    fn deref(&self) -> &Self::Target {
74        self.operands.deref()
75    }
76}
77
78impl<'a> IntoIterator for &'a ExprAnd {
79    type IntoIter = std::slice::Iter<'a, Expr>;
80    type Item = &'a Expr;
81
82    fn into_iter(self) -> Self::IntoIter {
83        self.operands.iter()
84    }
85}
86
87impl<'a> IntoIterator for &'a mut ExprAnd {
88    type IntoIter = std::slice::IterMut<'a, Expr>;
89    type Item = &'a mut Expr;
90
91    fn into_iter(self) -> Self::IntoIter {
92        self.operands.iter_mut()
93    }
94}
95
96impl From<ExprAnd> for Expr {
97    fn from(value: ExprAnd) -> Self {
98        Self::And(value)
99    }
100}
toasty_core/stmt/expr_and.rs

toasty_core/stmt/
expr_and.rs
