Python/互交模式
维基教科书,自由的教学读本
| Python介绍:
|
Python 有两个编辑基本模式:"command line"模式,编译脚本和完成的 .py 文件;另一种是"GUI"模式,当您输入一行指令系统都将返回关于你这条信息是否合法的信息,这个是包括以前代码一同调试的结果。过一段时间,每过一会儿 Python 都会将您输入的内容自动保存到硬盘。
如果进入GUI模式,比如键入"python"就将没有返回的参数,这是一个很好的方式,您可以用这种方式尝试变化对语法。
$ python Python 2.3.4 (#2, Aug 29 2004, 02:04:10) [GCC 3.3.4 (Debian 1:3.3.4-9)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>>
(如果 Python 没有正常运行,请您确认路径是否正确。参见 下载和安装 )
>>> 是 Python 告诉您该行字是表示您输入字符的符号。您将在系统提示语模块看到您输入字段程序运行的结果。尝试输入 1+1 . Python 将输出 2。如果您觉得您需要,请使用GUI模式。
例子:
>>> 5 5 >>> print 5*7 35 >>> "hello" * 4 'hellohellohellohello' >>> "hello".__class__ <type 'str'>
不过,您必须小心使用GUI模式。如果您不小心,混乱可能会接踵而至。下面是一个有效的Python脚本:
if 1: print "True" print "Done"
如果您的输入出现错误,会出现以下结果:
>>> if 1: ... print "True" ... print "Done" File "<stdin>", line 3 print "Done" ^ SyntaxError: invalid syntax
What the interpreter is saying is that the indentation of the second print was unexpected. What you should have entered was a blank line, to end the first (i.e., "if") statement, before you started writing the next print statement. For example, you should have entered the statements as though they were written:
if 1: print "True" print "Done"
Which would have resulted in the following:
>>> if 1: ... print "True" ... True >>> print "Done" Done >>>