If none of the other rule types will do, you can define your own
scoring function. “UDF“ stands for user-defined function: such a
function shall take a single parameter of type elfeed-entry
and
return either nil (to indicate no interest in this entry) or an
integer (representing this rule’s contribution to this entry’s score).
In the score file (see The Score File), UDF rules are represented by five properties:
:function
The user-defined function; typically this will be a
lambda
form or a symbol
:display-name
elfeed-score will attempt to deduce a name for
the function; if this value is specified, the given string will be
used for logging, pretty-print & so forth
:tags
Tag scoping rules
:feeds
Feed scoping rules
:comment
Comment