feat!: Drop returns bool, Put doesn't stack-overflow
#21
@@ -114,6 +114,9 @@ linters:
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# Reports uses of functions with replacement inside the testing package.
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# Reports uses of functions with replacement inside the testing package.
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- usetesting
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- usetesting
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# Reports mixed receiver types in structs/interfaces.
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- recvcheck
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settings:
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settings:
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revive:
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revive:
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rules:
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rules:
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@@ -2,7 +2,7 @@ package cuckoo
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// An EqualFunc determines whethers two keys are 'equal'. Keys that are 'equal'
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// An EqualFunc determines whethers two keys are 'equal'. Keys that are 'equal'
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// are teated as the same by the [Table]. A good EqualFunc is pure,
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// are teated as the same by the [Table]. A good EqualFunc is pure,
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// deterministic, and fast. By default, [NewTable] uses [DefaultEqualFunc].
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// deterministic, and fast. By default, [New] uses [DefaultEqualFunc].
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//
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//
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// This function MUST NOT return true if the [Hash] digest of two keys
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// This function MUST NOT return true if the [Hash] digest of two keys
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// are different: the [Table] will not work.
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// are different: the [Table] will not work.
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@@ -28,7 +28,7 @@ func ExampleEqualFunc_badEqualFunc() {
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// Two users with the same ID are equal.
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// Two users with the same ID are equal.
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isEqual := func(a, b User) bool { return a.ID == b.ID }
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isEqual := func(a, b User) bool { return a.ID == b.ID }
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userbase := cuckoo.NewCustomTable[User, bool](makeHash(1), makeHash(2), isEqual)
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userbase := cuckoo.NewCustom[User, bool](makeHash(1), makeHash(2), isEqual)
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(userbase.Put(User{"1", "Robert Doe"}, true))
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(userbase.Put(User{"1", "Robert Doe"}, true))
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@@ -56,7 +56,7 @@ func FuzzInsertLookup(f *testing.F) {
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fmt.Fprintf(os.Stderr, "seedA=%d seedB=%d capacity=%d growthFactor=%d\n",
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fmt.Fprintf(os.Stderr, "seedA=%d seedB=%d capacity=%d growthFactor=%d\n",
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seedA, seedB, capacity, growthFactor)
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seedA, seedB, capacity, growthFactor)
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actual := cuckoo.NewCustomTable[uint32, uint32](
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actual := cuckoo.NewCustom[uint32, uint32](
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offsetHash(seedA),
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offsetHash(seedA),
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offsetHash(seedB),
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offsetHash(seedB),
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func(a, b uint32) bool { return a == b },
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func(a, b uint32) bool { return a == b },
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@@ -74,16 +74,16 @@ func FuzzInsertLookup(f *testing.F) {
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delete(expected, step.key)
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delete(expected, step.key)
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_, err := actual.Get(step.key)
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_, ok = actual.Get(step.key)
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assert.Error(err)
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assert.True(ok)
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} else {
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} else {
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_, err := actual.Put(step.key, step.value)
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_, err := actual.Put(step.key, step.value)
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assert.NoError(err)
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assert.NoError(err)
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expected[step.key] = step.value
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expected[step.key] = step.value
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found, err := actual.Get(step.key)
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found, ok := actual.Get(step.key)
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assert.NoError(err)
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assert.True(ok)
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assert.Equal(step.value, found)
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assert.Equal(step.value, found)
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}
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}
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@@ -11,7 +11,7 @@ func TestMaxEvictions(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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for i := 16; i < 116; i++ {
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for i := 16; i < 116; i++ {
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table := NewTable[int, bool](Capacity(i / 2))
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table := New[int, bool](Capacity(i / 2))
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expectedEvictions := 3 * math.Floor(math.Log2(float64(i)))
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expectedEvictions := 3 * math.Floor(math.Log2(float64(i)))
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assert.Equal(table.maxEvictions(), int(expectedEvictions))
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assert.Equal(table.maxEvictions(), int(expectedEvictions))
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@@ -20,7 +20,7 @@ func TestMaxEvictions(t *testing.T) {
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func TestLoad(t *testing.T) {
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func TestLoad(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := NewTable[int, bool](Capacity(8))
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table := New[int, bool](Capacity(8))
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for i := range 16 {
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for i := range 16 {
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_, err := table.Put(i, true)
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_, err := table.Put(i, true)
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@@ -14,7 +14,7 @@ import (
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func TestNewTable(t *testing.T) {
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func TestNewTable(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTable[int, bool]()
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table := cuckoo.New[int, bool]()
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assert.NotNil(table)
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assert.NotNil(table)
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assert.Zero(table.Size())
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assert.Zero(table.Size())
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@@ -23,7 +23,7 @@ func TestNewTable(t *testing.T) {
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func TestAddItem(t *testing.T) {
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func TestAddItem(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key, value := 0, true
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key, value := 0, true
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table := cuckoo.NewTable[int, bool]()
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table := cuckoo.New[int, bool]()
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_, err := table.Put(key, value)
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_, err := table.Put(key, value)
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@@ -35,7 +35,7 @@ func TestAddItem(t *testing.T) {
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func TestPutOverwrite(t *testing.T) {
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func TestPutOverwrite(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key, value, newValue := 0, 1, 2
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key, value, newValue := 0, 1, 2
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table := cuckoo.NewTable[int, int]()
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table := cuckoo.New[int, int]()
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(table.Put(key, value))
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(table.Put(key, value))
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_, err := table.Put(key, newValue)
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_, err := table.Put(key, newValue)
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@@ -50,7 +50,7 @@ func TestPutOverwrite(t *testing.T) {
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func TestSameHash(t *testing.T) {
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func TestSameHash(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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hash := func(int) uint64 { return 0 }
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hash := func(int) uint64 { return 0 }
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table := cuckoo.NewCustomTable[int, bool](hash, hash, cuckoo.DefaultEqualFunc[int])
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table := cuckoo.NewCustom[int, bool](hash, hash, cuckoo.DefaultEqualFunc[int])
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_, errA := table.Put(0, true)
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_, errA := table.Put(0, true)
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_, errB := table.Put(1, true)
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_, errB := table.Put(1, true)
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@@ -63,14 +63,14 @@ func TestSameHash(t *testing.T) {
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func TestStartingCapacity(t *testing.T) {
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func TestStartingCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTable[int, bool](cuckoo.Capacity(64))
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table := cuckoo.New[int, bool](cuckoo.Capacity(64))
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assert.Equal(uint64(128), table.TotalCapacity())
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assert.Equal(uint64(128), table.TotalCapacity())
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}
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}
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func TestResizeCapacity(t *testing.T) {
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func TestResizeCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTable[int, bool](
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table := cuckoo.New[int, bool](
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cuckoo.Capacity(8),
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cuckoo.Capacity(8),
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cuckoo.GrowthFactor(2),
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cuckoo.GrowthFactor(2),
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)
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)
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@@ -85,7 +85,7 @@ func TestResizeCapacity(t *testing.T) {
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func TestPutMany(t *testing.T) {
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func TestPutMany(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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expected, actual := map[int]bool{}, cuckoo.NewTable[int, bool]()
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expected, actual := map[int]bool{}, cuckoo.New[int, bool]()
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for i := range 1_000 {
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for i := range 1_000 {
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expected[i] = true
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expected[i] = true
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@@ -100,7 +100,7 @@ func TestPutMany(t *testing.T) {
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func TestGetMany(t *testing.T) {
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func TestGetMany(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTable[int, bool]()
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table := cuckoo.New[int, bool]()
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for i := range 1_000 {
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for i := range 1_000 {
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_, err := table.Put(i, true)
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_, err := table.Put(i, true)
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@@ -108,12 +108,12 @@ func TestGetMany(t *testing.T) {
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}
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}
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for i := range 2_000 {
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for i := range 2_000 {
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value, err := table.Get(i)
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value, ok := table.Get(i)
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if i < 1_000 {
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if i < 1_000 {
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assert.NoError(err)
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assert.True(ok)
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assert.Equal(value, true)
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assert.Equal(value, true)
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} else {
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} else {
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assert.Error(err)
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assert.False(ok)
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}
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}
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}
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}
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}
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}
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@@ -121,7 +121,7 @@ func TestGetMany(t *testing.T) {
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func TestDropExistingItem(t *testing.T) {
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func TestDropExistingItem(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key, value := 0, true
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key, value := 0, true
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table := cuckoo.NewTable[int, bool]()
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table := cuckoo.New[int, bool]()
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(table.Put(key, value))
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(table.Put(key, value))
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had := table.Drop(key)
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had := table.Drop(key)
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@@ -134,7 +134,7 @@ func TestDropExistingItem(t *testing.T) {
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func TestDropNoItem(t *testing.T) {
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func TestDropNoItem(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key := 0
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key := 0
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table := cuckoo.NewTable[int, bool]()
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table := cuckoo.New[int, bool]()
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had := table.Drop(key)
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had := table.Drop(key)
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@@ -146,7 +146,7 @@ func TestDropNoItem(t *testing.T) {
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func TestDropItemCapacity(t *testing.T) {
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func TestDropItemCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key := 0
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key := 0
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table := cuckoo.NewTable[int, bool](
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table := cuckoo.New[int, bool](
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cuckoo.Capacity(64),
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cuckoo.Capacity(64),
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cuckoo.GrowthFactor(2),
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cuckoo.GrowthFactor(2),
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)
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)
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@@ -163,7 +163,7 @@ func TestDropItemCapacity(t *testing.T) {
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func TestPutNoCapacity(t *testing.T) {
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func TestPutNoCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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key, value := 0, true
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key, value := 0, true
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table := cuckoo.NewTable[int, bool](
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table := cuckoo.New[int, bool](
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cuckoo.Capacity(0),
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cuckoo.Capacity(0),
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)
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)
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@@ -176,7 +176,7 @@ func TestPutNoCapacity(t *testing.T) {
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func TestBadHashCapacity(t *testing.T) {
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func TestBadHashCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewCustomTable[int, bool](
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table := cuckoo.NewCustom[int, bool](
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func(int) uint64 { return 0 },
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func(int) uint64 { return 0 },
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func(int) uint64 { return 0 },
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func(int) uint64 { return 0 },
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func(a, b int) bool { return a == b },
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func(a, b int) bool { return a == b },
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@@ -196,7 +196,7 @@ func TestBadHashCapacity(t *testing.T) {
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func TestDropResizeCapacity(t *testing.T) {
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func TestDropResizeCapacity(t *testing.T) {
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTable[int, bool](
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table := cuckoo.New[int, bool](
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cuckoo.Capacity(10),
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cuckoo.Capacity(10),
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)
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)
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@@ -216,9 +216,7 @@ func TestNewTableBy(t *testing.T) {
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}
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}
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assert := assert.New(t)
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assert := assert.New(t)
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table := cuckoo.NewTableBy[User, bool](
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table := cuckoo.NewBy[User, bool](func(u User) string { return u.id })
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func(u User) string { return u.id },
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)
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_, err := table.Put(User{nil, "1", "Robert"}, true)
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_, err := table.Put(User{nil, "1", "Robert"}, true)
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4
doc.go
4
doc.go
@@ -1,8 +1,8 @@
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// Package cuckoo provides a hash table that uses cuckoo hashing to achieve
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// Package cuckoo provides a hash table that uses cuckoo hashing to achieve
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// a worst-case O(1) lookup time.
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// a worst-case O(1) lookup time.
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//
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//
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// While a [NewTable] only supports comparable keys by default, you can create
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// While a [New] only supports comparable keys by default, you can create
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// a table with any key type using [NewCustomTable]. Custom [Hash] functions and
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// a table with any key type using [NewCustom]. Custom [Hash] functions and
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// key comparison are also supported.
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// key comparison are also supported.
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//
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//
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// See more: https://en.wikipedia.org/wiki/Cuckoo_hashing
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// See more: https://en.wikipedia.org/wiki/Cuckoo_hashing
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@@ -8,25 +8,25 @@ import (
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)
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)
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func Example_basic() {
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func Example_basic() {
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table := cuckoo.NewTable[int, string]()
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table := cuckoo.New[int, string]()
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if _, err := table.Put(1, "Hello, World!"); err != nil {
|
if _, err := table.Put(1, "Hello, World!"); err != nil {
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fmt.Println("Put error:", err)
|
fmt.Println("Put error:", err)
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}
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}
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if item, err := table.Get(1); err != nil {
|
if item, ok := table.Get(1); !ok {
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fmt.Println("Error:", err)
|
fmt.Println("Not Found 1!")
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} else {
|
} else {
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fmt.Println("Found 1:", item)
|
fmt.Println("Found 1:", item)
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}
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}
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if item, err := table.Get(0); err != nil {
|
if item, ok := table.Get(0); !ok {
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fmt.Println("Error:", err)
|
fmt.Println("Not Found 0!")
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} else {
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} else {
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fmt.Println("Found 0:", item)
|
fmt.Println("Found 0:", item)
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}
|
}
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|
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// Output:
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// Output:
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// Found 1: Hello, World!
|
// Found 1: Hello, World!
|
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// Error: key '0' not found
|
// Not Found 0!
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}
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}
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@@ -9,7 +9,7 @@ import "fmt"
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const DefaultCapacity uint64 = 16
|
const DefaultCapacity uint64 = 16
|
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|
|
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// DefaultGrowthFactor is the standard resize multiplier for a [Table]. Most
|
// DefaultGrowthFactor is the standard resize multiplier for a [Table]. Most
|
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// hash table implementations use 2.
|
// implementations use 2.
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const DefaultGrowthFactor uint64 = 2
|
const DefaultGrowthFactor uint64 = 2
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|
|
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// defaultMinimumLoad is the default lowest acceptable occupancy of a [Table].
|
// defaultMinimumLoad is the default lowest acceptable occupancy of a [Table].
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@@ -31,10 +31,10 @@ type settings struct {
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|||||||
}
|
}
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|
|
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// An Option modifies the settings of a [Table]. It is used in its constructors
|
// An Option modifies the settings of a [Table]. It is used in its constructors
|
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// like [NewTable], for example.
|
// like [New], for example.
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type Option func(*settings)
|
type Option func(*settings)
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|
|
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// Capacity modifies the starting capacity of each bucket of the [Table]. The
|
// Capacity modifies the starting capacity of each subtable of the [Table]. The
|
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// value must be non-negative.
|
// value must be non-negative.
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func Capacity(value int) Option {
|
func Capacity(value int) Option {
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if value < 0 {
|
if value < 0 {
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|
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@@ -11,7 +11,7 @@ type slot[K, V any] struct {
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occupied bool
|
occupied bool
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}
|
}
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|
|
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type bucket[K, V any] struct {
|
type subtable[K, V any] struct {
|
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hash Hash[K]
|
hash Hash[K]
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slots []slot[K, V]
|
slots []slot[K, V]
|
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capacity, size uint64
|
capacity, size uint64
|
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@@ -20,11 +20,11 @@ type bucket[K, V any] struct {
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|
|
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// location determines where in the bucket a certain key would be placed. If the
|
// location determines where in the bucket a certain key would be placed. If the
|
||||||
// capacity is 0, this will panic.
|
// capacity is 0, this will panic.
|
||||||
func (b bucket[K, V]) location(key K) uint64 {
|
func (b *subtable[K, V]) location(key K) uint64 {
|
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return b.hash(key) % b.capacity
|
return b.hash(key) % b.capacity
|
||||||
}
|
}
|
||||||
|
|
||||||
func (b bucket[K, V]) get(key K) (value V, found bool) {
|
func (b *subtable[K, V]) get(key K) (value V, found bool) {
|
||||||
if b.capacity == 0 {
|
if b.capacity == 0 {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
@@ -33,7 +33,7 @@ func (b bucket[K, V]) get(key K) (value V, found bool) {
|
|||||||
return slot.Value, slot.occupied && b.compare(slot.Key, key)
|
return slot.Value, slot.occupied && b.compare(slot.Key, key)
|
||||||
}
|
}
|
||||||
|
|
||||||
func (b *bucket[K, V]) drop(key K) (occupied bool) {
|
func (b *subtable[K, V]) drop(key K) (occupied bool) {
|
||||||
if b.capacity == 0 {
|
if b.capacity == 0 {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
@@ -49,8 +49,8 @@ func (b *bucket[K, V]) drop(key K) (occupied bool) {
|
|||||||
return false
|
return false
|
||||||
}
|
}
|
||||||
|
|
||||||
func (b *bucket[K, V]) resized(capacity uint64) bucket[K, V] {
|
func (b *subtable[K, V]) resized(capacity uint64) *subtable[K, V] {
|
||||||
return bucket[K, V]{
|
return &subtable[K, V]{
|
||||||
slots: make([]slot[K, V], capacity),
|
slots: make([]slot[K, V], capacity),
|
||||||
capacity: capacity,
|
capacity: capacity,
|
||||||
hash: b.hash,
|
hash: b.hash,
|
||||||
@@ -58,7 +58,7 @@ func (b *bucket[K, V]) resized(capacity uint64) bucket[K, V] {
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
func (b bucket[K, V]) update(key K, value V) (updated bool) {
|
func (b *subtable[K, V]) update(key K, value V) (updated bool) {
|
||||||
if b.capacity == 0 {
|
if b.capacity == 0 {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
@@ -73,7 +73,7 @@ func (b bucket[K, V]) update(key K, value V) (updated bool) {
|
|||||||
return false
|
return false
|
||||||
}
|
}
|
||||||
|
|
||||||
func (b *bucket[K, V]) insert(insertion Entry[K, V]) (evicted Entry[K, V], eviction bool) {
|
func (b *subtable[K, V]) insert(insertion Entry[K, V]) (evicted Entry[K, V], eviction bool) {
|
||||||
if b.capacity == 0 {
|
if b.capacity == 0 {
|
||||||
return insertion, true
|
return insertion, true
|
||||||
}
|
}
|
||||||
@@ -96,8 +96,8 @@ func (b *bucket[K, V]) insert(insertion Entry[K, V]) (evicted Entry[K, V], evict
|
|||||||
return insertion, true
|
return insertion, true
|
||||||
}
|
}
|
||||||
|
|
||||||
func newBucket[K, V any](capacity uint64, hash Hash[K], compare EqualFunc[K]) bucket[K, V] {
|
func newSubtable[K, V any](capacity uint64, hash Hash[K], compare EqualFunc[K]) *subtable[K, V] {
|
||||||
return bucket[K, V]{
|
return &subtable[K, V]{
|
||||||
hash: hash,
|
hash: hash,
|
||||||
capacity: capacity,
|
capacity: capacity,
|
||||||
compare: compare,
|
compare: compare,
|
||||||
118
table.go
118
table.go
@@ -1,41 +1,50 @@
|
|||||||
package cuckoo
|
package cuckoo
|
||||||
|
|
||||||
import (
|
import (
|
||||||
|
"errors"
|
||||||
"fmt"
|
"fmt"
|
||||||
"iter"
|
"iter"
|
||||||
"math/bits"
|
"math/bits"
|
||||||
"strings"
|
"strings"
|
||||||
)
|
)
|
||||||
|
|
||||||
// A Table is hash table that uses cuckoo hashing to resolve collision. Create
|
// ErrBadHash occurs when the hashes given to a [Table] cause too many key
|
||||||
// one with [NewTable]. Or if you want more granularity, use [NewTableBy] or
|
// collisions. Try rebuilding the table using:
|
||||||
// [NewCustomTable].
|
//
|
||||||
|
// 1. Different hash seeds. Equal seeds produce equal hash functions, which
|
||||||
|
// always cycle.
|
||||||
|
// 2. A different [Hash] algorithm.
|
||||||
|
var ErrBadHash = errors.New("bad hash")
|
||||||
|
|
||||||
|
// A Table which uses cuckoo hashing to resolve collision. Create
|
||||||
|
// one with [New]. Or if you want more granularity, use [NewBy] or
|
||||||
|
// [NewCustom].
|
||||||
type Table[K, V any] struct {
|
type Table[K, V any] struct {
|
||||||
bucketA, bucketB bucket[K, V]
|
tableA, tableB *subtable[K, V]
|
||||||
growthFactor uint64
|
growthFactor uint64
|
||||||
minLoadFactor float64
|
minLoadFactor float64
|
||||||
}
|
}
|
||||||
|
|
||||||
// TotalCapacity returns the number of slots allocated for the [Table]. To get the
|
// TotalCapacity returns the number of slots allocated for the [Table]. To get the
|
||||||
// number of slots filled, look at [Table.Size].
|
// number of slots filled, look at [Table.Size].
|
||||||
func (t Table[K, V]) TotalCapacity() uint64 {
|
func (t *Table[K, V]) TotalCapacity() uint64 {
|
||||||
return t.bucketA.capacity + t.bucketB.capacity
|
return t.tableA.capacity + t.tableB.capacity
|
||||||
}
|
}
|
||||||
|
|
||||||
// Size returns how many slots are filled in the [Table].
|
// Size returns how many slots are filled in the [Table].
|
||||||
func (t Table[K, V]) Size() int {
|
func (t *Table[K, V]) Size() int {
|
||||||
return int(t.bucketA.size + t.bucketB.size)
|
return int(t.tableA.size + t.tableB.size)
|
||||||
}
|
}
|
||||||
|
|
||||||
func log2(n uint64) (m int) {
|
func log2(n uint64) (m int) {
|
||||||
return max(0, bits.Len64(n)-1)
|
return max(0, bits.Len64(n)-1)
|
||||||
}
|
}
|
||||||
|
|
||||||
func (t Table[K, V]) maxEvictions() int {
|
func (t *Table[K, V]) maxEvictions() int {
|
||||||
return 3 * log2(t.TotalCapacity())
|
return 3 * log2(t.TotalCapacity())
|
||||||
}
|
}
|
||||||
|
|
||||||
func (t Table[K, V]) load() float64 {
|
func (t *Table[K, V]) load() float64 {
|
||||||
// When there are no slots in the table, we still treat the load as 100%.
|
// When there are no slots in the table, we still treat the load as 100%.
|
||||||
// Every slot in the table is full.
|
// Every slot in the table is full.
|
||||||
if t.TotalCapacity() == 0 {
|
if t.TotalCapacity() == 0 {
|
||||||
@@ -49,20 +58,20 @@ func (t Table[K, V]) load() float64 {
|
|||||||
// size of the table. Returns a displaced entry and 'homeless = true' if an
|
// size of the table. Returns a displaced entry and 'homeless = true' if an
|
||||||
// entry could not be placed after exhausting evictions.
|
// entry could not be placed after exhausting evictions.
|
||||||
func (t *Table[K, V]) insert(entry Entry[K, V]) (displaced Entry[K, V], homeless bool) {
|
func (t *Table[K, V]) insert(entry Entry[K, V]) (displaced Entry[K, V], homeless bool) {
|
||||||
if t.bucketA.update(entry.Key, entry.Value) {
|
if t.tableA.update(entry.Key, entry.Value) {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
if t.bucketB.update(entry.Key, entry.Value) {
|
if t.tableB.update(entry.Key, entry.Value) {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
for range t.maxEvictions() {
|
for range t.maxEvictions() {
|
||||||
if entry, homeless = t.bucketA.insert(entry); !homeless {
|
if entry, homeless = t.tableA.insert(entry); !homeless {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
if entry, homeless = t.bucketB.insert(entry); !homeless {
|
if entry, homeless = t.tableB.insert(entry); !homeless {
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
@@ -72,12 +81,12 @@ func (t *Table[K, V]) insert(entry Entry[K, V]) (displaced Entry[K, V], homeless
|
|||||||
|
|
||||||
// resized creates an empty copy of the table, with a new capacity for each
|
// resized creates an empty copy of the table, with a new capacity for each
|
||||||
// bucket.
|
// bucket.
|
||||||
func (t Table[K, V]) resized(capacity uint64) Table[K, V] {
|
func (t *Table[K, V]) resized(capacity uint64) *Table[K, V] {
|
||||||
return Table[K, V]{
|
return &Table[K, V]{
|
||||||
growthFactor: t.growthFactor,
|
growthFactor: t.growthFactor,
|
||||||
minLoadFactor: t.minLoadFactor,
|
minLoadFactor: t.minLoadFactor,
|
||||||
bucketA: t.bucketA.resized(capacity),
|
tableA: t.tableA.resized(capacity),
|
||||||
bucketB: t.bucketB.resized(capacity),
|
tableB: t.tableB.resized(capacity),
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
@@ -93,11 +102,11 @@ func (t *Table[K, V]) resize(capacity uint64) bool {
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
*t = updated
|
*t = *updated
|
||||||
return true
|
return true
|
||||||
}
|
}
|
||||||
|
|
||||||
// grow increases the table's capacity by the [Table.growthFactor]. If the
|
// grow increases the table's capacity by the growth factor. If the
|
||||||
// capacity is 0, it increases it to 1.
|
// capacity is 0, it increases it to 1.
|
||||||
func (t *Table[K, V]) grow() bool {
|
func (t *Table[K, V]) grow() bool {
|
||||||
var newCapacity uint64
|
var newCapacity uint64
|
||||||
@@ -105,36 +114,43 @@ func (t *Table[K, V]) grow() bool {
|
|||||||
if t.TotalCapacity() == 0 {
|
if t.TotalCapacity() == 0 {
|
||||||
newCapacity = 1
|
newCapacity = 1
|
||||||
} else {
|
} else {
|
||||||
newCapacity = t.bucketA.capacity * t.growthFactor
|
newCapacity = t.tableA.capacity * t.growthFactor
|
||||||
}
|
}
|
||||||
|
|
||||||
return t.resize(newCapacity)
|
return t.resize(newCapacity)
|
||||||
}
|
}
|
||||||
|
|
||||||
// shrink reduces the table's capacity by the [Table.growthFactor]. It may
|
// shrink reduces the table's capacity by the growth factor. It may
|
||||||
// reduce it down to 0.
|
// reduce it down to 0.
|
||||||
func (t *Table[K, V]) shrink() bool {
|
func (t *Table[K, V]) shrink() bool {
|
||||||
return t.resize(t.bucketA.capacity / t.growthFactor)
|
return t.resize(t.tableA.capacity / t.growthFactor)
|
||||||
}
|
}
|
||||||
|
|
||||||
// Get fetches the value for a key in the [Table]. Returns an error if no value
|
// Get fetches the value for a key in the [Table]. Matches the comma-ok pattern
|
||||||
// is found.
|
// of a builtin map; see [Table.Find] for plain indexing.
|
||||||
func (t Table[K, V]) Get(key K) (value V, err error) {
|
func (t *Table[K, V]) Get(key K) (value V, ok bool) {
|
||||||
if item, ok := t.bucketA.get(key); ok {
|
if item, ok := t.tableA.get(key); ok {
|
||||||
return item, nil
|
return item, true
|
||||||
}
|
}
|
||||||
|
|
||||||
if item, ok := t.bucketB.get(key); ok {
|
if item, ok := t.tableB.get(key); ok {
|
||||||
return item, nil
|
return item, true
|
||||||
}
|
}
|
||||||
|
|
||||||
return value, fmt.Errorf("key '%v' not found", key)
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
// Find fetches the value of a key. Matches direct indexing of a builtin map;
|
||||||
|
// see [Table.Get] for a comma-ok pattern.
|
||||||
|
func (t *Table[K, V]) Find(key K) (value V) {
|
||||||
|
value, _ = t.Get(key)
|
||||||
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
// Has returns true if a key has a value in the table.
|
// Has returns true if a key has a value in the table.
|
||||||
func (t Table[K, V]) Has(key K) (exists bool) {
|
func (t *Table[K, V]) Has(key K) (exists bool) {
|
||||||
_, err := t.Get(key)
|
_, exists = t.Get(key)
|
||||||
return err == nil
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
// Put sets the value for a key. If it cannot be set, an error is returned,
|
// Put sets the value for a key. If it cannot be set, an error is returned,
|
||||||
@@ -174,7 +190,7 @@ func (t *Table[K, V]) Put(key K, value V) (displaced Entry[K, V], err error) {
|
|||||||
// Drop removes a value for a key in the table. Returns whether the key had
|
// Drop removes a value for a key in the table. Returns whether the key had
|
||||||
// existed.
|
// existed.
|
||||||
func (t *Table[K, V]) Drop(key K) bool {
|
func (t *Table[K, V]) Drop(key K) bool {
|
||||||
occupied := t.bucketA.drop(key) || t.bucketB.drop(key)
|
occupied := t.tableA.drop(key) || t.tableB.drop(key)
|
||||||
|
|
||||||
if t.load() < t.minLoadFactor {
|
if t.load() < t.minLoadFactor {
|
||||||
// The error is not handled here, because table-shrinking is an internal
|
// The error is not handled here, because table-shrinking is an internal
|
||||||
@@ -186,9 +202,9 @@ func (t *Table[K, V]) Drop(key K) bool {
|
|||||||
}
|
}
|
||||||
|
|
||||||
// Entries returns an unordered sequence of all key-value pairs in the table.
|
// Entries returns an unordered sequence of all key-value pairs in the table.
|
||||||
func (t Table[K, V]) Entries() iter.Seq2[K, V] {
|
func (t *Table[K, V]) Entries() iter.Seq2[K, V] {
|
||||||
return func(yield func(K, V) bool) {
|
return func(yield func(K, V) bool) {
|
||||||
for _, slot := range t.bucketA.slots {
|
for _, slot := range t.tableA.slots {
|
||||||
if slot.occupied {
|
if slot.occupied {
|
||||||
if !yield(slot.Key, slot.Value) {
|
if !yield(slot.Key, slot.Value) {
|
||||||
return
|
return
|
||||||
@@ -196,7 +212,7 @@ func (t Table[K, V]) Entries() iter.Seq2[K, V] {
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
for _, slot := range t.bucketB.slots {
|
for _, slot := range t.tableB.slots {
|
||||||
if slot.occupied {
|
if slot.occupied {
|
||||||
if !yield(slot.Key, slot.Value) {
|
if !yield(slot.Key, slot.Value) {
|
||||||
return
|
return
|
||||||
@@ -207,8 +223,8 @@ func (t Table[K, V]) Entries() iter.Seq2[K, V] {
|
|||||||
}
|
}
|
||||||
|
|
||||||
// String returns the entries of the table as a string in the format:
|
// String returns the entries of the table as a string in the format:
|
||||||
// "table[k1:v1 h2:v2 ...]".
|
// "table[k1:v1 k2:v2 ...]".
|
||||||
func (t Table[K, V]) String() string {
|
func (t *Table[K, V]) String() string {
|
||||||
var sb strings.Builder
|
var sb strings.Builder
|
||||||
sb.WriteString("table[")
|
sb.WriteString("table[")
|
||||||
|
|
||||||
@@ -226,9 +242,9 @@ func (t Table[K, V]) String() string {
|
|||||||
return sb.String()
|
return sb.String()
|
||||||
}
|
}
|
||||||
|
|
||||||
// NewCustomTable creates a [Table] with custom [Hash] and [EqualFunc]
|
// NewCustom creates a [Table] with custom [Hash] and [EqualFunc]
|
||||||
// functions, along with any [Option] the user provides.
|
// functions, along with any [Option] the user provides.
|
||||||
func NewCustomTable[K, V any](hashA, hashB Hash[K], compare EqualFunc[K], options ...Option) *Table[K, V] {
|
func NewCustom[K, V any](hashA, hashB Hash[K], compare EqualFunc[K], options ...Option) *Table[K, V] {
|
||||||
settings := &settings{
|
settings := &settings{
|
||||||
growthFactor: DefaultGrowthFactor,
|
growthFactor: DefaultGrowthFactor,
|
||||||
bucketSize: DefaultCapacity,
|
bucketSize: DefaultCapacity,
|
||||||
@@ -242,8 +258,8 @@ func NewCustomTable[K, V any](hashA, hashB Hash[K], compare EqualFunc[K], option
|
|||||||
return &Table[K, V]{
|
return &Table[K, V]{
|
||||||
growthFactor: settings.growthFactor,
|
growthFactor: settings.growthFactor,
|
||||||
minLoadFactor: settings.minLoadFactor,
|
minLoadFactor: settings.minLoadFactor,
|
||||||
bucketA: newBucket[K, V](settings.bucketSize, hashA, compare),
|
tableA: newSubtable[K, V](settings.bucketSize, hashA, compare),
|
||||||
bucketB: newBucket[K, V](settings.bucketSize, hashB, compare),
|
tableB: newSubtable[K, V](settings.bucketSize, hashB, compare),
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
@@ -251,10 +267,10 @@ func pipe[X, Y, Z any](a func(X) Y, b func(Y) Z) func(X) Z {
|
|||||||
return func(x X) Z { return b(a(x)) }
|
return func(x X) Z { return b(a(x)) }
|
||||||
}
|
}
|
||||||
|
|
||||||
// NewTableBy creates a [Table] for any key type by using keyFunc to derive a
|
// NewBy creates a [Table] for any key type by using keyFunc to derive a
|
||||||
// comparable key. Two keys with the same derived key are treated as equal.
|
// comparable key. Two keys with the same derived key are treated as equal.
|
||||||
func NewTableBy[K, V any, C comparable](keyFunc func(K) C, options ...Option) *Table[K, V] {
|
func NewBy[K, V any, C comparable](keyFunc func(K) C, options ...Option) *Table[K, V] {
|
||||||
return NewCustomTable[K, V](
|
return NewCustom[K, V](
|
||||||
pipe(keyFunc, NewDefaultHash[C]()),
|
pipe(keyFunc, NewDefaultHash[C]()),
|
||||||
pipe(keyFunc, NewDefaultHash[C]()),
|
pipe(keyFunc, NewDefaultHash[C]()),
|
||||||
func(a, b K) bool { return keyFunc(a) == keyFunc(b) },
|
func(a, b K) bool { return keyFunc(a) == keyFunc(b) },
|
||||||
@@ -262,10 +278,10 @@ func NewTableBy[K, V any, C comparable](keyFunc func(K) C, options ...Option) *T
|
|||||||
)
|
)
|
||||||
}
|
}
|
||||||
|
|
||||||
// NewTable creates a [Table] using the default [Hash] and [EqualFunc]. Use
|
// New creates a [Table] using the default [Hash] and [EqualFunc]. Use
|
||||||
// the [Option] functions to configure its behavior. Note that this constructor
|
// the [Option] functions to configure its behavior. Note that this constructor
|
||||||
// is only provided for comparable keys. For arbitrary keys, consider
|
// is only provided for comparable keys. For arbitrary keys, consider
|
||||||
// [NewTableBy] or [NewCustomTable].
|
// [NewBy] or [NewCustom].
|
||||||
func NewTable[K comparable, V any](options ...Option) *Table[K, V] {
|
func New[K comparable, V any](options ...Option) *Table[K, V] {
|
||||||
return NewCustomTable[K, V](NewDefaultHash[K](), NewDefaultHash[K](), DefaultEqualFunc[K], options...)
|
return NewCustom[K, V](NewDefaultHash[K](), NewDefaultHash[K](), DefaultEqualFunc[K], options...)
|
||||||
}
|
}
|
||||||
|
|||||||
Reference in New Issue
Block a user