diff --git a/include/proto/pattern.h b/include/proto/pattern.h
index 63e02e7..1424820 100644
--- a/include/proto/pattern.h
+++ b/include/proto/pattern.h
@@ -89,6 +89,16 @@
 
 /*
  *
+ * The following functions clean all entries of a pattern expression and
+ * reset the tree and list root.
+ *
+ */
+void pat_prune_val(struct pattern_expr *expr);
+void pat_prune_ptr(struct pattern_expr *expr);
+void pat_prune_reg(struct pattern_expr *expr);
+
+/*
+ *
  * The following functions are general purpose pattern matching functions.
  *
  */
@@ -172,11 +182,10 @@
 struct pattern *pat_match_reg(struct sample *smp, struct pattern_expr *expr, int fill);
 
 int pattern_read_from_file(struct pattern_expr *expr, const char *filename, int patflags, char **err);
-void pattern_free(struct pattern_list *pat);
-void pattern_prune_expr(struct pattern_expr *expr);
 void pattern_init_expr(struct pattern_expr *expr);
 int pattern_lookup(const char *args, struct pattern_expr *expr, struct pattern_list **pat_elt, struct pattern_tree **idx_elt, char **err);
 int pattern_delete(const char *key, struct pattern_expr *expr, char **err);
+void pattern_prune(struct pattern_expr *expr);
 
 
 #endif
diff --git a/include/types/acl.h b/include/types/acl.h
index 96b30bd..0a89c99 100644
--- a/include/types/acl.h
+++ b/include/types/acl.h
@@ -95,6 +95,7 @@
 	int (*parse)(const char *text, struct pattern *pattern, char **err);
 	int (*index)(struct pattern_expr *expr, struct pattern *pattern, char **err);
 	void (*delete)(struct pattern_expr *expr, struct pattern *pattern);
+	void (*prune)(struct pattern_expr *expr);
 	struct pattern *(*match)(struct sample *smp, struct pattern_expr *expr, int fill);
 	/* must be after the config params */
 	struct sample_fetch *smp; /* the sample fetch we depend on */
diff --git a/include/types/pattern.h b/include/types/pattern.h
index 2224e4c..966c83e 100644
--- a/include/types/pattern.h
+++ b/include/types/pattern.h
@@ -135,7 +135,6 @@
 		char *str;              /* any string  */
 		struct my_regex *reg;   /* a compiled regex */
 	} ptr;                          /* indirect values, allocated */
-	void(*freeptrbuf)(void *ptr);	/* a destructor able to free objects from the ptr */
 	int len;                        /* data length when required  */
 	int flags;                      /* expr or pattern flags. */
 	struct sample_storage *smp;     /* used to store a pointer to sample value associated
@@ -158,6 +157,7 @@
 	int (*parse)(const char *text, struct pattern *pattern, char **err);
 	int (*index)(struct pattern_expr *, struct pattern *, char **);
 	void (*delete)(struct pattern_expr *, struct pattern *);
+	void (*prune)(struct pattern_expr *);
 	struct pattern *(*match)(struct sample *, struct pattern_expr *, int);
 	struct list patterns;         /* list of acl_patterns */
 	struct eb_root pattern_tree;  /* may be used for lookup in large datasets */
@@ -168,6 +168,7 @@
 extern int (*pat_parse_fcts[PAT_MATCH_NUM])(const char *, struct pattern *, char **);
 extern int (*pat_index_fcts[PAT_MATCH_NUM])(struct pattern_expr *, struct pattern *, char **);
 extern void (*pat_delete_fcts[PAT_MATCH_NUM])(struct pattern_expr *, struct pattern *);
+void (*pat_prune_fcts[PAT_MATCH_NUM])(struct pattern_expr *);
 extern struct pattern *(*pat_match_fcts[PAT_MATCH_NUM])(struct sample *, struct pattern_expr *, int);
 extern int pat_match_types[PAT_MATCH_NUM];