xcode #定义负数？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/15870140/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
#define negative numbers?
提问by David
Simple question, but I cannot seem to find the answer. Is it okay to use #defineto define a negative number, as in:
简单的问题，但我似乎无法找到答案。是否可以使用#define定义负数，如：
#define kGravity -9.8
XCode is changing the 9.8 to the color of my numbers I have set (purple), but the -is being shown as the same color as the define statement (orange).
XCode 正在将 9.8 更改为我设置的数字的颜色（紫色），但-显示为与定义语句（橙色）相同的颜色。
Is this legal? Will it compile?
这是合法的吗？它会编译吗？
回答by Paul Armstrong
Did you try it? It should work fine.
你试了吗？它应该可以正常工作。
However, I would encourage you to not use pre-processor macros, but instead use real constants.
但是，我鼓励您不要使用预处理器宏，而是使用实常数。
static const float kGravity = -9.8f;
Preprocessor directives are a bit frowned upon, in general. Here's some more info on the subject: #define vs const in Objective-C
一般来说，预处理器指令有点不受欢迎。这里有一些关于这个主题的更多信息：#define vs const in Objective-C
回答by dasblinkenlight
It is absolutely legal to define negative constants with #define. What you discovered is most likely a bug in Xcode's code coloring, which will probably be fixed in one of the future revisions.
用 定义负常数是绝对合法的#define。您发现的很可能是 Xcode 代码着色中的一个错误，该错误可能会在未来的某个修订版中得到修复。
