Add method for delete by regex rule

cache.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"regexp"
 	"runtime"
 	"sync"
 	"time"
@@ -911,6 +912,16 @@ func (c *cache) Delete(k string) {
 	}
 }
 
+// Delete an item from the cache by regex rule
+func (c *cache) DeleteRegex(rule string) {
+	re, _ := regexp.Compile(rule)
+	for k := range c.items {
+		if re.MatchString(k) {
+			c.Delete(k)
+		}
+	}
+}
+
 func (c *cache) delete(k string) (interface{}, bool) {
 	if c.onEvicted != nil {
 		if v, found := c.items[k]; found {

cache_test.go

@@ -1150,6 +1150,19 @@ func TestDelete(t *testing.T) {
 	}
 }
 
+func TestDeleteRegex(t *testing.T) {
+	tc := New(DefaultExpiration, 0)
+	tc.Set("foo1", "bar", DefaultExpiration)
+	tc.DeleteRegex(`^foo`)
+	x, found := tc.Get("foo")
+	if found {
+		t.Error("foo was found, but it should have been deleted")
+	}
+	if x != nil {
+		t.Error("x is not nil:", x)
+	}
+}
+
 func TestItemCount(t *testing.T) {
 	tc := New(DefaultExpiration, 0)
 	tc.Set("foo", "1", DefaultExpiration)