From f300b00c2d89774339879140f3bb77c89690c30b Mon Sep 17 00:00:00 2001
From: Sarah Hoffmann <lonvia@denofr.de>
Date: Tue, 29 Jul 2025 22:59:02 +0200
Subject: [PATCH 1/2] docs: add a list of available topics

---
 docs/customize/Import-Styles.md | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/docs/customize/Import-Styles.md b/docs/customize/Import-Styles.md
index 01baf9b4..624f8541 100644
--- a/docs/customize/Import-Styles.md
+++ b/docs/customize/Import-Styles.md
@@ -36,18 +36,27 @@ local flex = require('flex-base')
 ### Using preset configurations
 
 If you want to start with one of the existing presets, then you can import
-its settings using the `import_topic()` function:
+its settings using the `load_topic()` function:
 
-```
+``` lua
 local flex = require('flex-base')
 
-flex.import_topic('streets')
+flex.load_topic('streets')
 ```
 
-The `import_topic` function takes an optional second configuration
+The `load_topic` function takes an optional second configuration
 parameter. The available options are explained in the
 [themepark section](#using-osm2pgsql-themepark).
 
+Available topics are: `admin`, `street`, `address`, `full`. These topic
+correspond to the [import styles](../admin/Import.md#filtering-imported-data)
+you can choose during import. To start with the 'extratags' style, use the
+`full` topic with the appropriate config parameter:
+
+``` lua
+flex.load_topic('full', {with_extratags = true})
+```
+
 !!! note
     You can also directly import the preset style files, e.g.
     `local flex = require('import-street')`. It is not possible to

From 69e882096c80a1bd8dd3926fb19a3b451178edbe Mon Sep 17 00:00:00 2001
From: Sarah Hoffmann <lonvia@denofr.de>
Date: Tue, 29 Jul 2025 23:04:14 +0200
Subject: [PATCH 2/2] clarify what merging means

---
 docs/customize/Import-Styles.md | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/docs/customize/Import-Styles.md b/docs/customize/Import-Styles.md
index 624f8541..954f173d 100644
--- a/docs/customize/Import-Styles.md
+++ b/docs/customize/Import-Styles.md
@@ -125,8 +125,10 @@ value without key, then this is used as default for values that are not listed.
 
 `set_main_tags()` will completely replace the current main tag configuration
 with the new configuration. `modify_main_tags()` will merge the new
-configuration with the existing one. Otherwise, the two functions do exactly
-the same.
+configuration with the existing one. Merging is done at value level.
+For example, when the current setting is `highway = {'always', primary = 'named'}`,
+then `set_main_tags{highway = 'delete'}` will result in a rule
+`highway = {'delete', primary = 'named'}`.
 
 !!! example
     ``` lua
@@ -143,9 +145,9 @@ the same.
     when it has a value of `administrative`. Objects with `highway` tags are
     always included with two exceptions: the troll tag `highway=no` is
     deleted on the spot. And when the value is `street_lamp` then the object
-    must have a name, too. Finally, if a `landuse` tag is present then
-    it will be used independently of the concrete value when neither boundary
-    nor highway tags were found and the object is named.
+    must also have a name, to be included. Finally, if a `landuse` tag is
+    present then it will be used independently of the concrete value when
+    neither boundary nor highway tags were found and the object is named.
 
 ##### Presets