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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. 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 ## 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. 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.