Prolog語法產生

Question

我想學習如何在prolog中編寫生產規則。 這就是我所擁有的。

paragraph --> sentence, paragraph ; []. 
sentence --> proper_noun, [ ], verb, [ ], preposition, [ ], article, [ ], noun, period. 
proper_noun --> [Jimmy] ; [Yancy] ; [Clementine] ; [Astrid]. 
verb --> [runs] ; [walks] ; [skips] ; [flies]. 
preposition --> [to] ; [at] ; [around] ; [through]. 
article --> [the] ; [a]. 
noun --> [school] ; [house] ; [car] ; [spaceship]. 
period -->[.]. 

我嘗試使用

phrase(sentence, [Jimmy," ",walks," ",to," ",the," ",school], []), atom_codes(Output,[Jimmy," ",walks," ",to," ",the," ",school]). 

它返回假爲輸出調用它。請幫助我瞭解我出錯的地方以及如何編寫更好的語法。

Answer 1

使用'Jimmy'等（即將所有以大寫字母開頭的原子放入引號中）。否則，它們被解釋爲邏輯變量。你確實會得到很多「單變量變量」警告。

你也錯過了一些括號，並提出了幾個錯別字：

paragraph --> sentence, (paragraph ; []). 
sentence --> proper_noun, verb, preposition, article, noun, period. 
proper_noun --> ['Jimmy'] ; ['Yancy'] ; ['Clementine'] ; ['Astrid']. 
verb --> [runs] ; [walks] ; [skips] ; [flies]. 
preposition --> [to] ; [at] ; [around] ; [through]. 
article --> [the] ; [a]. 
noun --> [school] ; [house] ; [car] ; [spaceship]. 
period -->[.]. 

測試它：

30 ?- phrase(sentence, ['Jimmy', walks, to, the, school, .], []). 
true ; 
false.