update at ES.74 Rule

add (Reason) and (Example) at (Prefer to declare a loop variable in the initializer part of as `for`-statement) Rule
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Ameen Ali 2015-09-22 22:03:46 +03:00
parent 2e5b16736b
commit 34e636c2f4

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@ -7212,11 +7212,15 @@ This will copy each elements of `vs` into `s`. Better
<a name="Res-for-init"></a> <a name="Res-for-init"></a>
### ES.74: Prefer to declare a loop variable in the initializer part of as `for`-statement ### ES.74: Prefer to declare a loop variable in the initializer part of as `for`-statement
**Reason**: ??? **Reason**: 1) By creating variables inside loops, you ensure their scope is restricted to inside the loop. It cannot be referenced nor called outside of the loop.
2) some dedicated optimization can be performed more efficiently by the compiler (most importantly register allocation), since it knows that the variable cannot be used outside of the loop. For example, no need to store the result for later re-use.
**Example**: **Example**:
??? for(int counter = 0; counter <= 10; counter++)
{
cout << counter << endl ;
}
**Enforcement**: ??? **Enforcement**: ???