risingwave_common/util/
functional.rs

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// Copyright 2025 RisingWave Labs
//
// Licensed 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.

#[easy_ext::ext(SameOrElseExt)]
pub impl<T: Eq> T {
    /// Check if `self` and `other` are equal, if so, return `self`, otherwise return the result of `f()`.
    fn same_or_else(self, other: T, f: impl FnOnce() -> T) -> T {
        if self == other { self } else { f() }
    }
}