Aspekte der morphologischen Analyse des Deutschen - Universität ...

Anhang C: Programmcode
/*********************************************************************************************************************************
word_segmentation(Atomlist:,Startstate:,
Index:,Segments:)
*********************************************************************************************************************************/
word_segmentation([],_State,_Index,Seg,Seg).
word_segmentation([Letter|Rest],State,I,SegsSoFar0,Segments) :-
non_failure_state(State,Letter,NonFailState),
transition(NonFailState,Letter,NewState),
output(NewState,WordList),
(WordList = [] -> % is the output function defined ?
SegsSoFar1 = SegsSoFar0
;
% yes, so convert the items in output into segments
( word_to_segment_conversion(WordList,I,NewSegments),
append(NewSegments,SegsSoFar0,SegsSoFar1)
)
),
J is I + 1,
word_segmentation(Rest,NewState,J,SegsSoFar1,Segments).
/*********************************************************************************************************************************
non_failure_state(State:,Letter:,NonFailState:)
NonFailState = State if there is transition from State with Letter
*********************************************************************************************************************************/
non_failure_state(State,Letter,State) :-
transition(State,Letter,NewState),
NewState \== fail,
!.
non_failure_state(State0,Letter,State) :-
transition(State0,Letter,fail), % no transition
f(State0,State1), % failure function
non_failure_state(State1,Letter,State).
/*********************************************************************************************************************************
transition(State1:,Char:,State2:):
State2 is the state which is reachable from State1 with Char.
if there isn't a transition then State2 = fail
*********************************************************************************************************************************/
transition(State1,AlphabetSymbol,fail) :-
\+ tr(State1,AlphabetSymbol,_),
!.
transition(State1,AlphabetSymbol,State2) :-
tr(State1,AlphabetSymbol,State2).
/*********************************************************************************************************************************
output(State:,WordList:):
Returns a list of morphs if the analysers output function is defined,
otherwise the empty list.
*********************************************************************************************************************************/
output(State,Wordlist) :-
(o(State,Wordlist) ->
true
;
Wordlist = []). % function undefined
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