related to #1693 changed smarty version to 4.1.0

include/smarty/docs/designers/language-basic-syntax/language-syntax-quotes.md

@@ -0,0 +1,61 @@
+Embedding Vars in Double Quotes {#language.syntax.quotes}
+===============================
+
+-   Smarty will recognize [assigned](#api.assign)
+    [variables](#language.syntax.variables) embedded in \"double
+    quotes\" so long as the variable name contains only numbers, letters
+    and under\_scores. See [naming](&url.php-manual;language.variables)
+    for more detail.
+
+-   With any other characters, for example a period(.) or
+    `$object->reference`, then the variable must be surrounded by
+    `` `backticks` ``.
+
+-   In addition Smarty3 does allow embedded Smarty tags in double quoted
+    strings. This is useful if you want to include variables with
+    modifiers, plugin or PHP function results.
+
+<!-- -->
+
+
+    {func var="test $foo test"}              // sees $foo
+    {func var="test $foo_bar test"}          // sees $foo_bar
+    {func var="test `$foo[0]` test"}         // sees $foo[0]
+    {func var="test `$foo[bar]` test"}       // sees $foo[bar]
+    {func var="test $foo.bar test"}          // sees $foo (not $foo.bar)
+    {func var="test `$foo.bar` test"}        // sees $foo.bar
+    {func var="test `$foo.bar` test"|escape} // modifiers outside quotes!
+    {func var="test {$foo|escape} test"}     // modifiers inside quotes!
+    {func var="test {time()} test"}          // PHP function result
+    {func var="test {counter} test"}         // plugin result
+    {func var="variable foo is {if !$foo}not {/if} defined"} // Smarty block function
+
+      
+
+
+    {* will replace $tpl_name with value *}
+    {include file="subdir/$tpl_name.tpl"}
+
+    {* does NOT replace $tpl_name *}
+    {include file='subdir/$tpl_name.tpl'} // vars require double quotes!
+
+    {* must have backticks as it contains a dot "." *}
+    {cycle values="one,two,`$smarty.config.myval`"}
+
+    {* must have backticks as it contains a dot "." *}
+    {include file="`$module.contact`.tpl"}
+
+    {* can use variable with dot syntax *}
+    {include file="`$module.$view`.tpl"}
+
+      
+
+> **Note**
+>
+> Although Smarty can handle some very complex expressions and syntax,
+> it is a good rule of thumb to keep the template syntax minimal and
+> focused on presentation. If you find your template syntax getting too
+> complex, it may be a good idea to move the bits that do not deal
+> explicitly with presentation to PHP by way of plugins or modifiers.
+
+See also [`escape`](#language.modifier.escape).