boa-cat 0.3.0

Tree-walking ECMAScript interpreter built on ecma-syntax-cat. v0.3.0 adds accessor-property support at the engine level: `Object::with_accessor(key, AccessorPair)` installs a getter/setter pair, and `obj.key` / `obj.key = value` dispatch through the pair instead of doing plain data read/write. Embedders (web-api-cat etc.) can now wire DOM accessors like `document.cookie` via native getter/setter functions. Object-literal `{ get x() {} }` syntax remains gated on ecma-parse-cat learning to emit `ObjectPropertyKind::Get/Set` (the engine handles those AST variants already).
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//! Completion records: the spec's abrupt-completion mechanism, lifted into
//! a sum type the interpreter can return from statement evaluation.

use crate::value::Value;

/// The result of evaluating a statement.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Completion {
    /// Normal completion with an optional value (the result of an
    /// `Expression` statement, the body of a block, etc.).
    Normal(Value),
    /// `return value;`
    Return(Value),
    /// `throw value;`
    Throw(Value),
    /// `break;` (labeled break deferred to v0.2).
    Break,
    /// `continue;` (labeled continue deferred to v0.2).
    Continue,
}

impl Completion {
    /// Whether this completion is abrupt (anything other than `Normal`).
    #[must_use]
    pub fn is_abrupt(&self) -> bool {
        !matches!(self, Self::Normal(_))
    }
}