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// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum ControlFlow<C, B> {
    Continue(C),
    Break(B),
}

impl<C, B> ControlFlow<C, B> {
    #[inline]
    pub fn is_break(&self) -> bool {
        matches!(*self, ControlFlow::Break(_))
    }

    #[inline]
    pub fn is_continue(&self) -> bool {
        matches!(*self, ControlFlow::Continue(_))
    }

    #[inline]
    pub fn break_value(self) -> Option<B> {
        match self {
            ControlFlow::Continue(..) => None,
            ControlFlow::Break(x) => Some(x),
        }
    }
}

impl<B> ControlFlow<(), B> {
    pub const CONTINUE: Self = ControlFlow::Continue(());
}

impl<C> ControlFlow<C, ()> {
    pub const BREAK: Self = ControlFlow::Break(());
}