Matches the "Content-Type" header of the stream to custom-defined accept rules. Returns true if the "Content-Type" header exists and the rules match its value, otherwise returns false. A stream without "Content-Type" header will be treated as "application/octet-stream".
The accept rules have the following format, in extended Backus-Naur form (EBNF) notation:
Match ::= Single ("," Single)* Single ::= Spaces? Type-Match ( Spaces? ";" Spaces? Parameter )* Spaces? Type-Match ::= "*/*" | Type "/*" | Type "/*+" Suffix | Type "/" Subtype 
 Parameter ::= Name "=" Value  | 
is-mime-content-type(s:stream, accept:string) -> Boolean  | 
Name  | 
Type  | 
Description  | 
|---|---|---|
s  | 
stream  | 
Specifies the input stream.  | 
accept  | 
string  | 
Specifies the custom-defined accept rules.  | 
The following expression will return true if stream msg contains the header Content-Type: text/html; charset=utf-8 or Content-Type: text/plain; charset=utf-8.
is-mime-content-type(msg, "text/*; charset=\"utf-8\"")  | 
The following expression will return true if stream msg contains the header Content-Type: application/rss+xml or Content-Type: application/svg+xml.
is-mime-content-type(msg, "application/*+xml")  | 
You can also match multiple rules by separating them with a comma. For example, the following expression will return true if stream msg contains the header Content-Type: text/xml or Content-Type: application/xml:
is-mime-content-type(msg, "text/xml, application/xml")  |