In normal situation, we can use ";" to show the next answer if there is one.
But if I do this, it shows me
error: char_code/2: Cannot represent due to 'character_code'
In stead of ";", I use "shift + ;", and prolog gives me a prompt
Unknown action: : (h for help) Action?
then if I input ";", the designable answers will be shown one by one.
What is the problem?
Use swipl-win.exe instead of swipl.exe can solve this problem.(I tried 6.x and 7.x)
By the way, swipl works well under MacOS.
来源：https://stackoverflow.com/questions/23133168/after-the-first-answer-prolog-shows-the-error-char-code-2-cannot-represent-du