print('x is positive') 1. 2. if 之后的布尔表达式被称作条件(condition)。 如果它为真,则缩进的语句会被执行。 如果不是,则什么也不会发生。 if 语句和函数定义有相同的结构:一个语句头跟着一个缩进的语句体。 类似的语句被称作复合语句(compound statements)。 语句体中可出现的语句数目没有限制,但是至少...
Yes No # --- -- if 'foo' in ['foo', 'bar', 'baz']: # x print('Outer condition is true') # x if 10 > 20: # x print('Inner condition 1') # x print('Between inner conditions') # x if 10 < 20: # x print('Inner condition 2') # x print('End of outer condition'...
They constitute the block that would be executed if the condition were true. But it is false, so all the statements in the block are skipped. After the end of the compound if statement has been reached (whether the statements in the block on lines 2 to 5 are executed or not), ...
如果某一条件用到了上述运算符,则称该条件为复合条件(Compound Condition)。复合条件的真假判断方式如下。假设A和B是两个条件,对于复合条件A and B来说,当且仅当二者均为真时,该复合条件为真,否则,该复合条件为假;对于复合条件A or B,当二者中有一个(或多个)为真时,该复合条件为真,否则,该复合条件为假;...
基本语法1. 简单的if语句ifcondition:# 如果 condition 为 True,执行这里的代码块statement(s)condition...
: IF compound_condition (suite)+ elif_clause* else_clause? | assignment ; suite : INDENT (compound_stmt)+ (DEDENT | EOF) ; 上面的语法中,INDENT和DEDENT就跟括号的处理没什么区别,只不过DEDENT可选,主要是考虑直接在代码后就EOF的情况。
if之后的布尔表达式称之为条件(condition),若为true,则后面缩进的语句(如上print)会执行,否则不会有任何动作。if语句和函数定义有相同结构:header后有一个缩进的body。此类语句称之为复合语句(compoundstatements)。body中不限制语句数量,但至少要有一个,若body中暂无语句而作为之后代码的保留位置,可用pass...
if (condition) { code } 1. 2. 3. 4. 5. 一个JavaScript代码片段的例子是这样的。 if (hour > 4) { task = "Clean the compound"; } 1. 2. 3. if-else 语句 在Python中,在else关键字后面写一个冒号(:)。 if condition: #if code ...
Another interesting use case for short-circuit evaluation is to avoid costly operations while creating compound logical expressions. For example, if you have a costly operation that should only run if a given condition is false, then you can use or like in the following snippet:Python data_is...
org/3/reference/compound_stmts.html#the-while-statement The while loop executes as long as the ...