39 lines
680 B
Go
39 lines
680 B
Go
package tag
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import (
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"maps"
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"slices"
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)
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// convenience shorthand for this awkward map type.
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type Set map[string]bool
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// add members to the "set"
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// TODO: this probably should have been a pointer receiver to handle the nil map case.
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// currently doing some roundabout checks before calling.
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func (s Set) Add(mems ...string) {
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for _, m := range mems {
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s[m] = true
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}
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}
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// get all members in a slice
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func (s Set) Members() []string {
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return slices.Collect(maps.Keys(s))
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}
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// s ∪ t
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func (s Set) Union(tt ...Set) {
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for _, t := range tt {
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s.Add(t.Members()...)
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}
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}
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// s ∩ t
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func (s Set) Intersect(t Set) {
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for m, _ := range s {
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if !t[m] {
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delete(s, m)
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}
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}
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}
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