add pointer receiver into all Functions methods

pkg/compiler/namespace.go

@@ -14,7 +14,7 @@ const emptyNS = ""
 const separator = "::"
 
 type NamespaceContainer struct {
-	funcs core.Functions
+	funcs *core.Functions
 	name  string
 }
 
@@ -25,7 +25,7 @@ func newRootNamespace() *NamespaceContainer {
 	return ns
 }
 
-func newNamespace(funcs core.Functions, name string) *NamespaceContainer {
+func newNamespace(funcs *core.Functions, name string) *NamespaceContainer {
 	return &NamespaceContainer{funcs, strings.ToUpper(name)}
 }
 

pkg/compiler/visitor.go

@@ -24,11 +24,11 @@ type (
 	visitor struct {
 		*fql.BaseFqlParserVisitor
 		src   string
-		funcs core.Functions
+		funcs *core.Functions
 	}
 )
 
-func newVisitor(src string, funcs core.Functions) *visitor {
+func newVisitor(src string, funcs *core.Functions) *visitor {
 	return &visitor{
 		&fql.BaseFqlParserVisitor{},
 		src,

pkg/runtime/core/function.go

@@ -48,38 +48,38 @@ type (
 )
 
 // NewFunctions returns new empty Functions.
-func NewFunctions() Functions {
-	return Functions{
+func NewFunctions() *Functions {
+	return &Functions{
 		functions: make(FunctionsMap),
 	}
 }
 
 // Get returns the function with the given name. If the function
 // does not exist it returns nil, false.
-func (fns Functions) Get(name string) (Function, bool) {
+func (fns *Functions) Get(name string) (Function, bool) {
 	fn, exists := fns.functions[strings.ToUpper(name)]
 	return fn, exists
 }
 
 // Set sets the function with the given name. If the function
 // with the such name already exists it will be overwritten.
-func (fns Functions) Set(name string, fn Function) {
+func (fns *Functions) Set(name string, fn Function) {
 	// the preferred way to create Functions is NewFunctions.
 	// But just in case, if someone creates differently
 	if fns.functions == nil {
-		fns.functions = make(FunctionsMap)
+		fns.functions = make(FunctionsMap, 1)
 	}
 
 	fns.functions[strings.ToUpper(name)] = fn
 }
 
 // Unset delete the function with the given name.
-func (fns Functions) Unset(name string) {
+func (fns *Functions) Unset(name string) {
 	delete(fns.functions, strings.ToUpper(name))
 }
 
 // Names returns the names of the internal functions.
-func (fns Functions) Names() []string {
+func (fns *Functions) Names() []string {
 	names := make([]string, 0, len(fns.functions))
 
 	for name := range fns.functions {