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Add note about underflow

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Closes #47
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Jason Turner
2016-05-25 15:50:11 -06:00
parent 75e12df808
commit 3bc2c04819
1 changed files with 10 additions and 0 deletions
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03-Style.md
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@@ -296,6 +296,16 @@ In general, using `auto` will avoid most of these issues, but not all.
Make sure you stick with the correct integer types and remain consistent with the C++ standard library. It might not warn on the platform you are currently using, but it probably will when you change platforms.
*Note that you can cause integer underflow when peforming some operations on unsigned values. For example:*
```cpp
std::vector<int> v1{2,3,4,5,6,7,8,9};
std::vector<int> v2{9,8,7,6,5,4,3,2,1};
const auto s1 = v1.size();
const auto s2 = v2.size();
const auto diff = s1 - s2; // diff underflows to a very large number
```
## Use .hpp and .cpp for Your File Extensions
Ultimately this is a matter of preference, but .hpp and .cpp are widely recognized by various editors and tools. So the choice is pragmatic. Specifically, Visual Studio only automatically recognizes .cpp and .cxx for C++ files, and Vim doesn't necessarily recognize .cc as a C++ file.