您被通用的Perl解析陷阱所困扰.您的第三条语句print ("a") x 2解析为:

You are being bitten by a common Perl parsing gotcha. Your third statement print ("a") x 2 is parsed as:

(print ("a")) x 2;

您可以添加另一组括号来修复该解析:

You can add another set of parentheses to fix the parsing:

print (("a") x 2);  # prints aa