diff --git a/src/exprlib.c b/src/exprlib.c
index 64bd7f3..f3f0b0c 100644
--- a/src/exprlib.c
+++ b/src/exprlib.c
@@ -492,7 +492,7 @@ static value_t expr_ident ( vm_t *vm, value_t p[], int np )
   return result;
 }
 
-static value_t action_gettext ( vm_t *vm, value_t p[], gint np )
+static value_t expr_gettext ( vm_t *vm, value_t p[], gint np )
 {
   vm_param_check_np_range(vm, np, 1, 2, "GT");
   vm_param_check_string(vm, p, 0, "GT");
@@ -503,7 +503,7 @@ static value_t action_gettext ( vm_t *vm, value_t p[], gint np )
         np==2? value_get_string(p[1]) : "sfwbar", value_get_string(p[0]))));
 }
 
-static value_t action_array_build ( vm_t *vm, value_t p[], gint np )
+static value_t expr_array_build ( vm_t *vm, value_t p[], gint np )
 {
   GArray *array;
   value_t v1;
@@ -521,13 +521,13 @@ static value_t action_array_build ( vm_t *vm, value_t p[], gint np )
   return value_new_array(array);
 }
 
-static value_t action_array_index ( vm_t *vm, value_t p[], gint np )
+static value_t expr_array_index ( vm_t *vm, value_t p[], gint np )
 {
   vm_param_check_np(vm, np, 2, "ArrayIndex");
   vm_param_check_array(vm, p, 0, "ArrayIndex");
   vm_param_check_numeric(vm, p, 1, "ArrayIndex");
 
-  if(!value_is_array(p[0]) ||
+  if(!value_is_array(p[0]) || (gint)value_get_numeric(p[1])<0 ||
       p[0].value.array->len <= ((gint)value_get_numeric(p[1])))
   return value_na;
 
@@ -535,9 +535,10 @@ static value_t action_array_index ( vm_t *vm, value_t p[], gint np )
       (gint)value_get_numeric(p[1]));
 }
 
-static value_t action_array_assign ( vm_t *vm, value_t p[], gint np )
+static value_t expr_array_assign ( vm_t *vm, value_t p[], gint np )
 {
-  value_t *v1, varr;
+  value_t *v1;
+  GArray *arr;
   gint n;
 
   vm_param_check_np(vm, np, 3, "ArrayAssign");
@@ -547,16 +548,30 @@ static value_t action_array_assign ( vm_t *vm, value_t p[], gint np )
   if(!value_is_array(p[0]))
     return value_na;
 
-  varr = value_dup(p[0]);
+  arr = g_array_ref(p[0].value.array);
   n = (gint)value_get_numeric(p[1]);
-  if(p[0].value.array->len <= n)
-    g_array_set_size(varr.value.array, n+1);
+  if(n<0 || n>=arr->len)
+    g_array_set_size(arr, n+1);
 
-  v1 = &g_array_index(varr.value.array, value_t, n);
+  v1 = &g_array_index(arr, value_t, n);
   value_free(*v1);
   *v1 = value_dup(p[2]);
 
-  return varr;
+  return value_new_array(arr);
+}
+
+static value_t expr_array_concat ( vm_t *vm, value_t p[], gint np )
+{
+  vm_param_check_np(vm, np, 2, "ArrayConcat");
+
+  return value_array_concat(p[0], p[1]);
+}
+
+static value_t expr_array_size ( vm_t *vm, value_t p[], gint np )
+{
+  vm_param_check_np(vm, np, 1, "ArraySize");
+
+  return value_new_numeric(value_is_array(p[0])? p[0].value.array->len : 0);
 }
 
 void expr_lib_init ( void )
@@ -588,8 +603,10 @@ void expr_lib_init ( void )
   vm_func_add("windowinfo", expr_lib_window_info, FALSE);
   vm_func_add("read", expr_lib_read, FALSE);
   vm_func_add("interfaceprovider", expr_iface_provider, FALSE);
-  vm_func_add("gt", action_gettext, FALSE);
-  vm_func_add("arraybuild", action_array_build, FALSE);
-  vm_func_add("arrayindex", action_array_index, FALSE);
-  vm_func_add("arrayassign", action_array_assign, FALSE);
+  vm_func_add("gt", expr_gettext, FALSE);
+  vm_func_add("arraybuild", expr_array_build, FALSE);
+  vm_func_add("arrayindex", expr_array_index, FALSE);
+  vm_func_add("arrayassign", expr_array_assign, FALSE);
+  vm_func_add("arrayconcat", expr_array_concat, FALSE);
+  vm_func_add("arraysize", expr_array_size, FALSE);
 }
diff --git a/src/vm/parser.c b/src/vm/parser.c
index afbc4dc..c561694 100644
--- a/src/vm/parser.c
+++ b/src/vm/parser.c
@@ -242,10 +242,9 @@ static gboolean parser_identifier ( GScanner *scanner, GByteArray *code )
   return TRUE;
 }
 
-static gboolean parser_list_handle ( GScanner *scanner, GByteArray *code )
+static gboolean parser_array_handle ( GScanner *scanner, GByteArray *code )
 {
-  guint8 data[sizeof(gpointer)+2], np = 0;
-  gconstpointer ptr;
+  guint8 np = 0;
 
   if(g_scanner_peek_next_token(scanner)!=']')
     do {
@@ -257,11 +256,7 @@ static gboolean parser_list_handle ( GScanner *scanner, GByteArray *code )
   if(!config_expect_token(scanner, ']', "Expected ']' at the end of the list"))
     return FALSE;
 
-  data[0]=EXPR_OP_FUNCTION;
-  data[1]=np;
-  ptr = vm_func_lookup("arraybuild");
-  memcpy(data+2, &ptr, sizeof(gpointer));
-  g_byte_array_append(code, data, sizeof(gpointer)+2);
+  parser_emit_function(code, vm_func_lookup("arraybuild"), np);
 
   return TRUE;
 }
@@ -280,7 +275,7 @@ static gboolean parser_value ( GScanner *scanner, GByteArray *code )
   else if(token == G_TOKEN_STRING)
     parser_emit_string(code, scanner->value.v_string);
   else if(token == '[')
-    parser_list_handle(scanner, code);
+    parser_array_handle(scanner, code);
   else if(token == G_TOKEN_IDENTIFIER)
     return parser_identifier(scanner, code);
   else if(token == '+')
@@ -429,7 +424,6 @@ static gboolean parser_action_parse ( GScanner *scanner, GByteArray *code )
 {
   gconstpointer ptr;
   gboolean neg;
-  guint8 data[sizeof(gpointer)+2];
   static guint8 discard = EXPR_OP_DISCARD;
   gint alen, flag, cond = 0, np = 0;
 
@@ -457,11 +451,7 @@ static gboolean parser_action_parse ( GScanner *scanner, GByteArray *code )
     parser_emit_numeric(code, cond & 0xff);
     parser_emit_numeric(code, cond>>8);
 
-    ptr = vm_func_lookup("checkstate");
-    memcpy(data+2, &ptr, sizeof(gpointer));
-    data[0]=EXPR_OP_FUNCTION;
-    data[1]=2;
-    g_byte_array_append(code, data, sizeof(gpointer)+2);
+    parser_emit_function(code, vm_func_lookup("checkstate"), 2);
     alen = parser_emit_jump(code, EXPR_OP_JZ);
   }
 
@@ -478,9 +468,6 @@ static gboolean parser_action_parse ( GScanner *scanner, GByteArray *code )
 
   if(!cond && parser_local_lookup(scanner))
     return parser_assign_parse(scanner, code);
-/*  if(!cond && scanner->token==G_TOKEN_IDENTIFIER &&
-      g_scanner_peek_next_token(scanner)=='=')
-    return parser_assign_parse(scanner, code);*/
 
   if( !config_lookup_next_key(scanner, config_toplevel_keys) &&
       !config_lookup_next_key(scanner, config_prop_keys) &&
@@ -499,10 +486,7 @@ static gboolean parser_action_parse ( GScanner *scanner, GByteArray *code )
 
   config_check_and_consume(scanner, ';');
 
-  memcpy(data+2, &ptr, sizeof(gpointer));
-  data[0]=EXPR_OP_FUNCTION;
-  data[1]=np;
-  g_byte_array_append(code, data, sizeof(gpointer)+2);
+  parser_emit_function(code, ptr, np);
 
   if(cond)
   {
diff --git a/src/vm/value.c b/src/vm/value.c
index 51ae705..93fa0cd 100644
--- a/src/vm/value.c
+++ b/src/vm/value.c
@@ -9,6 +9,21 @@ void value_free ( value_t v1 )
     g_array_unref(v1.value.array);
 }
 
+value_t value_array_concat ( value_t v1, value_t v2 )
+{
+  if(!value_is_array(v1) && !value_is_array(v1))
+    return value_na;
+
+  if(!value_is_array(v1))
+    return value_new_array(g_array_prepend_vals(g_array_ref(v2.value.array),
+          &v1, 1));
+  if(!value_is_array(v2))
+    return value_new_array(g_array_append_vals(g_array_ref(v1.value.array),
+          &v2, 1));
+  return value_new_array(g_array_append_vals(g_array_ref(v1.value.array),
+          v2.value.array->data, v2.value.array->len));
+}
+
 value_t value_dup_array ( value_t v1 )
 {
   GArray *array;
diff --git a/src/vm/value.h b/src/vm/value.h
index cb15f2c..5aa85e3 100644
--- a/src/vm/value.h
+++ b/src/vm/value.h
@@ -48,8 +48,8 @@ extern const value_t value_na;
 #define value_as_numeric(v) (value_like_numeric(v)? value_get_numeric(v) : \
     (value_is_string(v)? g_ascii_strtod(v.value.string, NULL) : 0))
 
-//#define value_free(v) { if(value_is_string(v)) g_free(v.value.string); }
 void value_free ( value_t );
 value_t value_dup ( value_t );
+value_t value_array_concat ( value_t v1, value_t v2 );
 
 #endif
diff --git a/src/vm/vm.c b/src/vm/vm.c
index e9fec3e..f359df6 100644
--- a/src/vm/vm.c
+++ b/src/vm/vm.c
@@ -53,6 +53,9 @@ static gboolean vm_op_binary ( vm_t *vm )
   if(value_is_na(v1) && value_is_na(v2))
     result = value_na;
 
+  else if(value_is_array(v1) || value_is_array(v2))
+    result = value_array_concat(v1, v2);
+
   else if(value_like_string(v1) && value_like_string(v2))
   {
     if(op == '+')