note that you don't always have to use %concat()

"+" is usually better.

diff --git a/doc/antora/modules/reference/pages/xlat/builtin.adoc b/doc/antora/modules/reference/pages/xlat/builtin.adoc
index fce3e64bec758ec456ed9a94015604b774e4b6cf..acdb42d7f18a367f6fb6718df2a7b1a1db206ad8 100644 (file)
--- a/doc/antora/modules/reference/pages/xlat/builtin.adoc
+++ b/doc/antora/modules/reference/pages/xlat/builtin.adoc
@@ -320,6 +320,9 @@ Used to join two or more attributes, separated by an optional delimiter.
 
 .Return: _string_
 
+In most cases, `%concat(...)` is only useful inside of a dynamically
+expanded string.  If you need to concatenate strings together in a policy, just use `+`.
+
 .Example
 
 [source,unlang]
@@ -343,6 +346,17 @@ aaa, bb, c
 aaa,bb,c
 ```
 
+.Using "+"
+[source,unlang]
+----
+string foo
+
+&foo += { "a", "c", "c", "d" } # abcd
+
+&foo += &control.Tmp-String-0[*]
+----
+
+
 === %explode(<&ref> <delim>)
 
 Split an string into multiple new strings based on a delimiter.