str_char (String,Char) (string,char)
(i,o) (o,i)
str_int (String,Int) (string,integer)
(i,o) (o,i)
char_int (Char,Int) (char,integer) (i,o)
(o,i)
frontchar (String,FrontChar,RestString)
(string,char,string) (i,x,x) (x,i,i)
fronttoken (String,Token,Rest) (string,string,string)
(i,o,o) (i,i,o) (o,i,i)
prologtoken (String,Token,Rest) (string,string,string)
(i,o,o) (i,i,o) (o,i,i)
isname (String) (string) (i)
concat (Str1,Str2,ResStr) (string,string,string)
(i,i,o)
str_len (String,Length) (string,integer)
(i,o)
frontstr (StrLen,String,FrontStr,RestStr)
(i,i,o,o)