Added simple context objects

simple-func-store.go

@@ -0,0 +1,66 @@
+// simple-var-store.go
+package expr
+
+import "fmt"
+
+type FuncTemplate func(ctx exprContext, name string, args []any) (result any, err error)
+
+type SimpleFuncStore struct {
+	varStore  map[string]any
+	funcStore map[string]FuncTemplate
+}
+
+type funcInfo struct {
+	name string
+	// minArgs int
+	// maxArgs int
+}
+
+func (info *funcInfo) Name() string {
+	return info.name
+}
+
+func (info *funcInfo) MinArgs() int {
+	return 0
+}
+
+func (info *funcInfo) MaxArgs() int {
+	return -1
+}
+
+func NewSimpleFuncStore() *SimpleFuncStore {
+	return &SimpleFuncStore{
+		varStore:  make(map[string]any),
+		funcStore: make(map[string]FuncTemplate),
+	}
+}
+
+func (ctx *SimpleFuncStore) GetValue(varName string) (v any, exists bool) {
+	v, exists = ctx.varStore[varName]
+	return
+}
+
+func (ctx *SimpleFuncStore) SetValue(varName string, value any) {
+	ctx.varStore[varName] = value
+}
+
+func (ctx *SimpleFuncStore) GetFuncInfo(name string) (f exprFunc) {
+	var exists bool
+	if _, exists = ctx.funcStore[name]; exists {
+		f = &funcInfo{name: name}
+	}
+	return
+}
+
+func (ctx *SimpleFuncStore) addFunc(name string, f FuncTemplate) {
+	ctx.funcStore[name] = f
+}
+
+func (ctx *SimpleFuncStore) Call(name string, args []any) (result any, err error) {
+	if f, exists := ctx.funcStore[name]; exists {
+		result, err = f(ctx, name, args)
+	} else {
+		err = fmt.Errorf("unknown function %s()", name)
+	}
+	return
+}

simple-var-store.go

@@ -0,0 +1,29 @@
+// simple-var-store.go
+package expr
+
+type SimpleVarStore struct {
+	store map[string]any
+}
+
+func NewSimpleVarStore() *SimpleVarStore {
+	return &SimpleVarStore{
+		store: make(map[string]any),
+	}
+}
+
+func (ctx *SimpleVarStore) GetValue(varName string) (v any, exists bool) {
+	v, exists = ctx.store[varName]
+	return
+}
+
+func (ctx *SimpleVarStore) SetValue(varName string, value any) {
+	ctx.store[varName] = value
+}
+
+func (ctx *SimpleVarStore) GetFuncInfo(name string) (f exprFunc) {
+	return
+}
+
+func (ctx *SimpleVarStore) Call(name string, args []any) (result any, err error) {
+	return
+}