2.3 变量名和关键字(Variable names and keywords) 程序员通常选择有意义的名称来命名变量,并对所用的变量进行归档。 变量名可包含字母和数字,但须以字母开始。虽然可以使用大写字母,但最好以小写字母开始变量名。 变量名中可以出现下划线(_),常用于有多个单词的变量名中,如my_name或airspeed_of_unladen_swallow....
Following the rules above, let’s review both valid and invalid variable names: ValidInvalidWhy Invalid my_intmy-intHyphens are not permitted int44intCannot begin with a number MY_INT$MY_INTCannot use symbols other than_ another_intanother intCannot be more than one word Something else to ke...
17.ValueError: invalid literal for int() with base 10: '3.14' 试图用int来转换一个字符串,而字符串包含的却是一个浮点数。 i = int("3.14") 如何修改: # 先转换成浮点数,再转换为整型 i = int(float("3.14")) # 或者 i = int(eval("3.14")) 18.UnboundLocalError: local variable 'x' refer...
SyntaxError: invalid syntax Python is a case sensitive programming language. Thus, Lastname and lastname are two different variable names in Python. Python是一种区分大小写的编程语言。因此,Lastname和Lastname是Python中两个不同的变量名。 Variables#变量 Trying to reference a variable you haven't assi...
How to Solve Python Invalid Syntax by Variable Names In Python, there are some rules for declaring a variable, and if you break that rule, then it will throw an invalid syntax error in Python. Let’s understand which types of rules we should follow while declaring a variable in Python wit...
Python variable names can include letters, digits, and underscores but can’t start with a digit. You should use snake case for multi-word names to improve readability. Variables exist in different scopes (global, local, non-local, or built-in), which affects how you can access them. You...
Valid variable names in Python Variables in Python can be made up of letters, numbers, and underscores: >>>user_name1="trey" Thefirst character in a variable cannot be a number: >>>1user="uhoh"File"<stdin>", line11user="uhoh"^SyntaxError:invalid decimal literal ...
~, etc. If we try to declare names with a special symbol, Python generates an error Example ca$h = 1000 Run Output ca$h = 11 ^ SyntaxError: invalid syntax Rule 4: Variable and constant should not start with digit letters. You will receive an error if you start a variable name with...
envValue int Environment variable value, which can be true or false output: ret int Operation result """ logging.info("Set the value of envZtpStatus to {} .".format(envValue)) if envValue not in ['true', 'false']: logging.error("The envValue:%s is invalid, not in ['true', '...
Additionally, variable names can only contain letters, numbers, and underscores, and variable names must begin with a letter or an underscore. Names like 1Aw)) or &^%^&^111 are not valid. Furthermore, it is recommended to avoid using abbreviations or overly simple names for variables in la...