{{'param1'|functionName}}

{{$tmpStr|
strlen
}}

{{'param1'|functionName:'param2'}}
{$tmpStr|substr:'1'}

{{'param1'|functionName:'param2':'param3'..}} 
{{$tmpStr|substr:'1':'2'}}
{{'a'|str_replace:'A':$tmpStr}}

$smarty->assign('tmpStr','');
smarty代码：
{{if $tmpStr|strlen > 0 }}
    1
{{else}}
    0
{{/if}}

$smarty->assign('tmpArr',array(1,2,3,4,5));

{{if $tmpArr|is_array && $tmpArr|@count > 0}}    
{{$tmpArr|@count}}{{else}}    
0
{{/if}}

$smarty->assign('tmpStr','abb');
{{'b'|str_replace:'c':$tmpStr}}

acc

$smarty->assign('tmpStr','abb');
{{$tmpStr|substr:'1'}}

bb

{{$tmpStr|substr:'1':'1'}}

b