Add stmutil containers and ContextDoneVar

4 files changed, 354 insertions, 0 deletions

diff --git a/go.mod b/go.mod
index 5d98f96..8813ebb 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,8 @@
 module github.com/lukechampine/stm
 
 go 1.13
+
+require (
+	github.com/anacrolix/missinggo/v2 v2.2.0
+	github.com/benbjohnson/immutable v0.2.0
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..99fdc4b
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,152 @@
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diff --git a/stmutil/containers.go b/stmutil/containers.go
new file mode 100644
index 0000000..89f7b05
--- /dev/null
+++ b/stmutil/containers.go
@@ -0,0 +1,180 @@
+package stmutil
+
+import (
+	"unsafe"
+
+	"github.com/benbjohnson/immutable"
+
+	"github.com/anacrolix/missinggo/v2/iter"
+)
+
+type Settish interface {
+	Add(interface{}) Settish
+	Delete(interface{}) Settish
+	Contains(interface{}) bool
+	Range(func(interface{}) bool)
+	iter.Iterable
+	Len() int
+}
+
+type mapToSet struct {
+	m Mappish
+}
+
+type interhash struct{}
+
+func (interhash) Hash(x interface{}) uint32 {
+	return uint32(nilinterhash(unsafe.Pointer(&x), 0))
+}
+
+func (interhash) Equal(i, j interface{}) bool {
+	return i == j
+}
+
+func NewSet() Settish {
+	return mapToSet{NewMap()}
+}
+
+func NewSortedSet(lesser lessFunc) Settish {
+	return mapToSet{NewSortedMap(lesser)}
+}
+
+func (s mapToSet) Add(x interface{}) Settish {
+	s.m = s.m.Set(x, nil)
+	return s
+}
+
+func (s mapToSet) Delete(x interface{}) Settish {
+	s.m = s.m.Delete(x)
+	return s
+}
+
+func (s mapToSet) Len() int {
+	return s.m.Len()
+}
+
+func (s mapToSet) Contains(x interface{}) bool {
+	_, ok := s.m.Get(x)
+	return ok
+}
+
+func (s mapToSet) Range(f func(interface{}) bool) {
+	s.m.Range(func(k, _ interface{}) bool {
+		return f(k)
+	})
+}
+
+func (s mapToSet) Iter(cb iter.Callback) {
+	s.Range(cb)
+}
+
+type Map struct {
+	*immutable.Map
+}
+
+func NewMap() Mappish {
+	return Map{immutable.NewMap(interhash{})}
+}
+
+var _ Mappish = Map{}
+
+func (m Map) Delete(x interface{}) Mappish {
+	m.Map = m.Map.Delete(x)
+	return m
+}
+
+func (m Map) Set(key, value interface{}) Mappish {
+	m.Map = m.Map.Set(key, value)
+	return m
+}
+
+func (sm Map) Range(f func(key, value interface{}) bool) {
+	iter := sm.Map.Iterator()
+	for !iter.Done() {
+		if !f(iter.Next()) {
+			return
+		}
+	}
+}
+
+func (sm Map) Iter(cb iter.Callback) {
+	sm.Range(func(key, _ interface{}) bool {
+		return cb(key)
+	})
+}
+
+type SortedMap struct {
+	*immutable.SortedMap
+}
+
+func (sm SortedMap) Set(key, value interface{}) Mappish {
+	sm.SortedMap = sm.SortedMap.Set(key, value)
+	return sm
+}
+
+func (sm SortedMap) Delete(key interface{}) Mappish {
+	sm.SortedMap = sm.SortedMap.Delete(key)
+	return sm
+}
+
+func (sm SortedMap) Range(f func(key, value interface{}) bool) {
+	iter := sm.SortedMap.Iterator()
+	for !iter.Done() {
+		if !f(iter.Next()) {
+			return
+		}
+	}
+}
+
+func (sm SortedMap) Iter(cb iter.Callback) {
+	sm.Range(func(key, _ interface{}) bool {
+		return cb(key)
+	})
+}
+
+type lessFunc func(l, r interface{}) bool
+
+type comparer struct {
+	less lessFunc
+}
+
+func (me comparer) Compare(i, j interface{}) int {
+	if me.less(i, j) {
+		return -1
+	} else if me.less(j, i) {
+		return 1
+	} else {
+		return 0
+	}
+}
+
+func NewSortedMap(less lessFunc) Mappish {
+	return SortedMap{
+		SortedMap: immutable.NewSortedMap(comparer{less}),
+	}
+}
+
+type Mappish interface {
+	Set(key, value interface{}) Mappish
+	Delete(key interface{}) Mappish
+	Get(key interface{}) (interface{}, bool)
+	Range(func(_, _ interface{}) bool)
+	Len() int
+	iter.Iterable
+}
+
+func GetLeft(l, _ interface{}) interface{} {
+	return l
+}
+
+//go:noescape
+//go:linkname nilinterhash runtime.nilinterhash
+func nilinterhash(p unsafe.Pointer, h uintptr) uintptr
+
+func interfaceHash(x interface{}) uint32 {
+	return uint32(nilinterhash(unsafe.Pointer(&x), 0))
+}
+
+type Lenner interface {
+	Len() int
+}
diff --git a/stmutil/context.go b/stmutil/context.go
new file mode 100644
index 0000000..49f211c
--- /dev/null
+++ b/stmutil/context.go
@@ -0,0 +1,17 @@
+package stmutil
+
+import (
+	"context"
+
+	"github.com/lukechampine/stm"
+)
+
+func ContextDoneVar(ctx context.Context) (*stm.Var, func()) {
+	ctx, cancel := context.WithCancel(ctx)
+	_var := stm.NewVar(false)
+	go func() {
+		<-ctx.Done()
+		stm.AtomicSet(_var, true)
+	}()
+	return _var, cancel
+}