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3.1 Statements and Blocks 语句与程序块
An expression such as x = 0 or i++ or printf(...) becomes a statement when it is followed by a semicolon, as in
x = 0; i++; printf(...);
In C, the semicolon is a statement terminator, rather than a separator as it is in languages like Pascal.
在x=0、i++或printf(...)这样的表达式之后加上一个分号(;),它们就变成了语句。例如:
x = 0; i++; printf(...);
在C语言中,分号是语句结束符,而Pascal等语言却把分号用作语句之间的分隔符。
Braces { and } are used to group declarations and statements together into a compound statement, or block, so that they are syntactically equivalent to a single statement. The braces that surround the statements of a function are one obvious example; braces around multiple statements after an if, else, while, or for are another. (Variables can be declared inside any block; we will talk about this in Chapter 4.) There is no semicolon after the right brace that ends a block.
用一对花括号“{”与“}”把一组声明和语句括在一起就构成了一个复合语句(也叫作程序块),复合语句在语法上等价于单条语句。函数体中被花括号括起来的语句便是明显一例。(在任何程序块中都可以声明变量,第4章将对此进行讨论。)右花括号用于结束程序块,其后不需要分号。