freemarker 0.1.1

Apache FreeMarker 语义兼容的 Rust 模板引擎(freemarker-core 迁移)
Documentation
//! 逻辑非 —— 对应 Java `freemarker.core.NotExpression`
//! (`evalToBoolean` → modelToBoolean 取反)

use crate::core::eval::{eval, model_to_boolean};
use crate::core::Expr;
use crate::error::Result;
use crate::template::TModel;

/// 逻辑非(对应 NotExpression.java;解析器经 `ExprKind::Not` 承载)
pub struct NotExpression {
    pub target: Expr,
}

impl NotExpression {
    /// 构造(Java 构造器;Rust 侧由解析器产生)
    pub fn new(target: Expr) -> Self {
        NotExpression { target }
    }

    /// 求值(Java `evalToBoolean` → modelToBoolean(classic 兼容见 eval.rs))
    pub(crate) fn eval(&self, env: &mut crate::core::Environment) -> Result<TModel> {
        let m = eval(env, &self.target)?;
        let b = model_to_boolean(env, &m)?;
        Ok(TModel::from_boolean(!b))
    }
}