njord 0.5.0

A versatile, feature-rich Rust ORM.
Documentation 
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//! BSD 3-Clause License
//!
//! Copyright (c) 2024,
//!     Marcus Cvjeticanin
//!     Chase Willden
//!
//! Redistribution and use in source and binary forms, with or without
//! modification, are permitted provided that the following conditions are met:
//!
//! 1. Redistributions of source code must retain the above copyright notice, this
//!    list of conditions and the following disclaimer.
//!
//! 2. Redistributions in binary form must reproduce the above copyright notice,
//!    this list of conditions and the following disclaimer in the documentation
//!    and/or other materials provided with the distribution.
//!
//! 3. Neither the name of the copyright holder nor the names of its
//!    contributors may be used to endorse or promote products derived from
//!    this software without specific prior written permission.
//!
//! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
//! AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
//! IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//! DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
//! FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
//! DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
//! SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
//! CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
//! OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
//! OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

/// The `QueryBuilder` trait.
///
/// Primarily used for subqueries within conditions.
pub trait QueryBuilder<'a>: QueryBuilderClone<'a> {
    fn to_sql(&self) -> String;
}

/// A helper trait to enable cloning of `Box<dyn QueryBuilder>`
pub trait QueryBuilderClone<'a> {
    fn clone_box(&self) -> Box<dyn QueryBuilder<'a> + 'a>;
}

impl<'a, T> QueryBuilderClone<'a> for T
where
    T: 'a + QueryBuilder<'a> + Clone,
{
    fn clone_box(&self) -> Box<dyn QueryBuilder<'a> + 'a> {
        Box::new(self.clone())
    }
}

impl<'a> Clone for Box<dyn QueryBuilder<'a> + 'a> {
    fn clone(&self) -> Box<dyn QueryBuilder<'a> + 'a> {
        self.clone_box()
    }
}