完成第一节Loop Statements的翻译
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Shindo
@ -50,7 +50,11 @@ for `initialzation`; `condition`; `increment` {
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}
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```
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<<<<<<< HEAD
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*initialzation*、*condition*和*increment*之间的分号，以及包围循环体*statements*的大括号都是不可省略的。
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=======
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*initialzation*、*condition*和*increment*之间的分号，以及包围在循环体*statements*的大括号都是不可省略的。
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>>>>>>> 完成第一节Loop Statements的翻译
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`for`语句的执行流程如下：
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@ -59,15 +63,25 @@ for `initialzation`; `condition`; `increment` {
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2. 计算*condition*表达式：
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如果为真(`true`)，*statements*将会被执行，然后转到第3步。如果为假(`false`)，*statements*和*increment*都不会被执行，`for`至此执行完毕。
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<<<<<<< HEAD
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3. 计算*increment*表达式，然后转到第2步。
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=======
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3. 执行*increment*表达式，然后转到第2步。
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>>>>>>> 完成第一节Loop Statements的翻译
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定义在*initialzation*中的变量仅在`for`语句的作用域以内有效。*condition*表达式的值的类型必须符合`LogicValue`协议。
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> GRAMMAR OF A FOR STATEMENT
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<<<<<<< HEAD
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> *for-statement* → **for** [*for-init*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Statements.html#//apple_ref/swift/grammar/for-init) *opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt* [*code-block*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/code-block)
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> *for-statement* → **for ( ** [*for-init*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Statements.html#//apple_ref/swift/grammar/for-init) *opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt* **)** [*code-block*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/code-block)
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=======
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> *for-statement* → **for** [*for-init*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Statements.html#//apple_ref/swift/grammar/for-init)*opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression)*opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression)*opt* [*code-block*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/code-block)
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> *for-statement* → **for ( ** [*for-init*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Statements.html#//apple_ref/swift/grammar/for-init)*opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression)*opt* **;** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression)*opt* **)** [*code-block*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/code-block)
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>>>>>>> 完成第一节Loop Statements的翻译
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> *for-statement* → [*variable-declaration*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/variable-declaration) | [*expression-list*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression-list)
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@ -110,7 +124,11 @@ while `condition` {
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由于*condition*的值在*statements*执行前就已计算出，因此*while*语句中的*statements*可能会被执行若干次，也可能不会被执行。
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<<<<<<< HEAD
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*condition*表达式的值的类型必须符合`LogicValue`协议。同时，*condition*表达式也可以使用可选绑定，请参考[可选绑定`待添加链接`]()。
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=======
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*condition*表达式的值的类型必须符合`LogicValue`协议。同时，*condition*表达式也可以套用可选绑定，请参考[可选绑定`待添加链接`]()。
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>>>>>>> 完成第一节Loop Statements的翻译
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> GRAMMAR OF A WHILE STATEMENT
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@ -139,6 +157,7 @@ do {
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由于*condition*表达式的值是在*statements*表达式执行后才计算出，因此*do-while*语句中的*statements*至少会被执行一次。
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<<<<<<< HEAD
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*condition*表达式的值的类型必须符合`LogicValue`协议。同时，*condition*表达式也可以使用可选绑定，请参考[可选绑定`待添加链接`]()。
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> GRAMMAR OF A DO-WHILE STATEMENT
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@ -372,4 +391,11 @@ return `表达式`
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> GRAMMAR OF A RETURN STATEMENT
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> *return-statement* → **return** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt*
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> *return-statement* → **return** [*expression*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/expression) *opt*
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=======
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*condition*表达式的值的类型必须符合`LogicValue`协议。同时，*condition*表达式也可以套用可选绑定，请参考[可选绑定`待添加链接`]()。
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> GRAMMAR OF A DO-WHILE STATEMENT
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> *do-while-statement* → **do** [*code-block*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Declarations.html#//apple_ref/swift/grammar/code-block) **while** [*while-condition*](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Statements.html#//apple_ref/swift/grammar/while-condition)
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>>>>>>> 完成第一节Loop Statements的翻译
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