rpn: remove duplicate metricRegistry, use ops.MetricRegistry()

3 files changed, 12 insertions, 16 deletions

diff --git a/internal/rpn/operations_interfaces.go b/internal/rpn/operations_interfaces.go
index 6af0973..b254a26 100644
--- a/internal/rpn/operations_interfaces.go
+++ b/internal/rpn/operations_interfaces.go
@@ -102,4 +102,6 @@ type Operator interface {
 	CustomList(stack *Stack) (string, error)
 	CustomDefine(name string, factor float64, category string) error
 	CustomUndefine(name string) error
+	// MetricRegistry returns the metric registry used by this Operations instance.
+	MetricRegistry() *MetricRegistry
 }
diff --git a/internal/rpn/rpn_parse.go b/internal/rpn/rpn_parse.go
index 8775f93..007ec00 100644
--- a/internal/rpn/rpn_parse.go
+++ b/internal/rpn/rpn_parse.go
@@ -483,7 +483,7 @@ func (r *RPN) pushLiteral(stack *Stack, token string) (bool, error) {
 	}
 
 	// Check if it's a number with a metric suffix (e.g., 100Mbps, 5.5GB, 2hr)
-	if num, metric, ok := parseNumberWithMetric(token, r.metricRegistry); ok {
+	if num, metric, ok := parseNumberWithMetric(token, r.ops.MetricRegistry()); ok {
 		if stack.Len() >= r.maxStack {
 			return false, fmt.Errorf("stack overflow")
 		}
@@ -495,7 +495,7 @@ func (r *RPN) pushLiteral(stack *Stack, token string) (bool, error) {
 	// Pushes a Number with value 1 and the looked-up metric
 	if len(token) > 1 && token[0] == '@' {
 		metricName := token[1:]
-		if metric, ok := r.metricRegistry.FindWithAliases(metricName); ok {
+		if metric, ok := r.ops.MetricRegistry().FindWithAliases(metricName); ok {
 			if stack.Len() >= r.maxStack {
 				return false, fmt.Errorf("stack overflow")
 			}
diff --git a/internal/rpn/rpn_state.go b/internal/rpn/rpn_state.go
index 647b5c3..474f164 100644
--- a/internal/rpn/rpn_state.go
+++ b/internal/rpn/rpn_state.go
@@ -19,29 +19,23 @@ type RPN struct {
 	assignHandler  *assignmentHandler
 	maxStack       int
 	currentStack   *Stack
-	metricRegistry *MetricRegistry
 }
 
 // NewRPN creates a new RPN parser and evaluator with the given variable store.
 // If no registry is provided, defaults to the global MetricRegistry.
 func NewRPN(vars VariableStore, reg ...*MetricRegistry) *RPN {
 	consts := NewConstants()
-	r := GetMetricRegistry()
-	if len(reg) > 0 && reg[0] != nil {
-		r = reg[0]
-	}
-	ops := NewOperations(vars, r)
+	ops := NewOperations(vars, reg...)
 	ops.SetMode(FloatMode) // Set default mode
 	ops.SetConstants(consts) // Share the same ConstantsProvider
 	return &RPN{
-		vars:           vars,
-		consts:         consts,
-		ops:            ops,
-		opRegistry:     NewOperatorRegistry(ops),
-		assignHandler:  newAssignmentHandler(),
-		maxStack:       1000, // Reasonable limit for RPN expressions
-		currentStack:   NewStack(),
-		metricRegistry: r,
+		vars:          vars,
+		consts:        consts,
+		ops:           ops,
+		opRegistry:    NewOperatorRegistry(ops),
+		assignHandler: newAssignmentHandler(),
+		maxStack:      1000, // Reasonable limit for RPN expressions
+		currentStack:  NewStack(),
 	}
 }