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Concatenation: oxy_concat() Function

This function concatenates the received string arguments.

Syntax:
oxy_concat ( str_1 , str_2 )
str_1 … str_n
The string arguments to be concatenated.

Example: oxy_concat Function

If an XML element has a @padding-left attribute:
 <p padding-left="20">...
and you want to add a padding before it with that specific amount specified in the attribute value:
*[padding-left]{
 padding-left:oxy_concat(attr(padding-left), "px");
}