Prolog中字符串的串联 [英] Concatenation of Strings in Prolog

问题描述

我正在尝试在Prolog中连接4个字符串。我可以连接2个和3个字符串，但无法使其与4个字符串一起使用。到目前为止，这就是我的意思：

I am trying to concatenate 4 strings in Prolog. I am able to concatenate 2 and 3 strings but I can't get it to work with 4. This is what I have so far:

join2(String1,String2,Newstring) :-
   name(String1,L1), name(String2,L2),
   append(L1,L2,Newlist),
   name(Newstring,Newlist).

join3(String1,String2,String3,Newstring) :-
   join2(String1,String2,S),
   join2(S,String3,Newstring).

join4(String1,String2,String3,String4,Newstring) :-
   join3(String1,String2,String3,Newstring),
     join2(String1,String2,S),
     join2(S,String3,Newstring).
   join3(Newstring,String4,Newstring).

推荐答案

我不确定您的约束是什么，但是您还可以使用SWI的 append / 2 和 maplist / 3 ：

I'm not sure what your constraints are, but you can also use SWI's append/2 and maplist/3:

concatenate(StringList, StringResult) :-
    maplist(atom_chars, StringList, Lists),
    append(Lists, List),
    atom_chars(StringResult, List).

然后，您可以连接任意数量的：

Then you can concatenate as many as you like:

?- concatenate(["hello", ", ", "world"], String).
String = 'hello, world'.

?- concatenate(["hey, ", "you ", "don't ", "say!"], String).
String = 'hey, you don\'t say!'.

?-

请注意，以上假定您使用的是 SWI Prolog中的> 默认设置：

Note that the above assumes you are using the default setting in SWI Prolog:

:- set_prolog_flag(double_quotes,atom).

其中 abc 表示Prolog原子相当于'abc'。

where "abc" represents a Prolog atom and is equivalent to 'abc'.

这篇关于Prolog中字符串的串联的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！