trigger: allow creation of temporary variables with the regex

ChangeLog.adoc

@@ -22,6 +22,7 @@ New features::
 
   * core: allow partial buffer name in command /buffer close (issue #1226)
   * api: add function hook_line
+  * trigger: allow creation of temporary variables with the regex
 
 Bug fixes::
 

doc/de/weechat_user.de.adoc

@@ -3797,7 +3797,12 @@ ${tg_displayed} && (${tg_highlight} || ${tg_msg_pv})
 Reguläre Ausdrücke werden verwendet um Variablen in einem Callback Hashtable zu ändern.
 
 Das Format ist: "/regex/replace" oder "/regex/replace/var" (wobei _var_ eine
-Variable eines Hashtable darstellt). +
+Variable eines Hashtable darstellt).
+
+// TRANSLATION MISSING
+If _var_ does not exist in the hashtable, it is created automatically with an
+empty value. This allows to create custom temporary variables.
+
 Sollte _var_ nicht näher spezifiziert sein, wird die Standard-Variable genutzt,
 welche abhängig von dem genutzten Hook ist:
 

doc/en/weechat_user.en.adoc

@@ -3711,7 +3711,11 @@ ${tg_displayed} && (${tg_highlight} || ${tg_msg_pv})
 The regular expression is used to change variables in callback hashtable.
 
 The format is: "/regex/replace" or "/regex/replace/var" (where _var_ is a
-variable of the hashtable). +
+variable of the hashtable).
+
+If _var_ does not exist in the hashtable, it is created automatically with an
+empty value. This allows to create custom temporary variables.
+
 If _var_ is not specified, the default variable is used, it depends on hook
 type:
 

doc/fr/weechat_user.fr.adoc

@@ -3830,7 +3830,11 @@ L'expression régulière est utilisée pour modifier des variables dans la table
 de hachage de la fonction de rappel.
 
 Le format est : "/regex/remplacement" ou "/regex/remplacement/var" (où _var_ est
-une variable de la table de hachage). +
+une variable de la table de hachage).
+
+Si _var_ n'existe pas dans la table de hachage, elle est automatiquement créée
+avec une valeur vide. Cela permet de créer des variables temporaires.
+
 Si _var_ n'est pas spécifiée, la variable par défaut est utilisée, elle dépend
 du type de hook :
 

doc/it/weechat_user.it.adoc

@@ -3971,7 +3971,12 @@ ${tg_displayed} && (${tg_highlight} || ${tg_msg_pv})
 The regular expression is used to change variables in callback hashtable.
 
 The format is: "/regex/replace" or "/regex/replace/var" (where _var_ is a
-variable of the hashtable). +
+variable of the hashtable).
+
+// TRANSLATION MISSING
+If _var_ does not exist in the hashtable, it is created automatically with an
+empty value. This allows to create custom temporary variables.
+
 If _var_ is not specified, the default variable is used, it depends on hook
 type:
 

doc/ja/weechat_user.ja.adoc

@@ -3707,7 +3707,12 @@ ${tg_displayed} && (${tg_highlight} || ${tg_msg_pv})
 正規表現はコールバックハッシュテーブル内の変数を変更するために使われます。
 
 書式: "/regex/replace" または "/regex/replace/var" (ここで
-_var_ はハッシュテーブルの変数)。 +
+_var_ はハッシュテーブルの変数)。
+
+// TRANSLATION MISSING
+If _var_ does not exist in the hashtable, it is created automatically with an
+empty value. This allows to create custom temporary variables.
+
 _var_
 が指定されなかった場合、デフォルト変数を使います、これはフックの種類に依存します:
 

doc/pl/weechat_user.pl.adoc

@@ -3741,7 +3741,12 @@ ${tg_displayed} && (${tg_highlight} || ${tg_msg_pv})
 Wyrażenia regularne są używane do zmiany zmiennych w tablicy hashy callbacka.
 
 Format: "/wyrażenie/zamień" lub "/wyrażenie/zamień/zmienna" (gdzie _zmienna_ to
-zmienna tablicy hashy). +
+zmienna tablicy hashy).
+
+// TRANSLATION MISSING
+If _var_ does not exist in the hashtable, it is created automatically with an
+empty value. This allows to create custom temporary variables.
+
 Jeśli _zmienna_ nie zostanie podana, użyta zostanie domyślna zmienna, zależy ona
 od typu uchwytu:
 

src/plugins/trigger/trigger-callback.c

@@ -277,9 +277,10 @@ trigger_callback_replace_regex (struct t_trigger *trigger,
             {
                 weechat_printf_date_tags (trigger_buffer, 0, "no_trigger",
                                           "\t  regex %d (%s): %s",
-                                          i + 1, ptr_key, _("empty variable"));
+                                          i + 1, ptr_key, _("creating variable"));
             }
-            continue;
+            weechat_hashtable_set (extra_vars, ptr_key, "");
+            ptr_value = weechat_hashtable_get (extra_vars, ptr_key);
         }
 
         weechat_hashtable_set (pointers, "regex", trigger->regex[i].regex);