48 lines
1.2 KiB
Go
48 lines
1.2 KiB
Go
/*
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Copyright 2014 Google Inc. All rights reserved.
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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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http://www.apache.org/licenses/LICENSE-2.0
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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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*/
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package util
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type empty struct{}
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// A set of strings, implemented via map[string]struct{} for minimal memory consumption.
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type StringSet map[string]empty
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// NewStringSet creates a StringSet from a list of values.
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func NewStringSet(items ...string) StringSet {
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ss := StringSet{}
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ss.Insert(items...)
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return ss
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}
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// Insert adds items to the set.
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func (s StringSet) Insert(items ...string) {
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for _, item := range items {
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s[item] = empty{}
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}
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}
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// Delete removes item from the set.
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func (s StringSet) Delete(item string) {
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delete(s, item)
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}
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// Has returns true iff item is contained in the set.
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func (s StringSet) Has(item string) bool {
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_, contained := s[item]
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return contained
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}
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