54 lines
1.4 KiB
Rust
54 lines
1.4 KiB
Rust
// This file is part of Substrate.
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// Copyright (C) Parity Technologies (UK) Ltd.
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// SPDX-License-Identifier: Apache-2.0
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//! Produce opaque sequential IDs.
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/// A Sequence of IDs.
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#[derive(Debug, Default)]
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// The `Clone` trait is intentionally not defined on this type.
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pub struct IDSequence {
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next_id: u64,
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}
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/// A Sequential ID.
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///
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/// Its integer value is intentionally not public: it is supposed to be instantiated from within
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/// this module only.
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#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct SeqID(u64);
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impl std::fmt::Display for SeqID {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(f, "{}", self.0)
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}
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}
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impl IDSequence {
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/// Create a new ID-sequence.
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pub fn new() -> Self {
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Default::default()
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}
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/// Obtain another ID from this sequence.
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pub fn next_id(&mut self) -> SeqID {
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let id = SeqID(self.next_id);
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self.next_id += 1;
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id
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}
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}
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