inline

C++ Shorten subsequent function calls

由 。_饼干妹妹 提交于 2019-12-05 23:15:21
I try to find a way in C++17 to shorten following function calls: GetCurrentContext()->GetEntityManager()->CreateEntity(); maybe to something like: EM()->CreateEntity(); I tried a function pointer, but this is only valid for static functions: constexpr auto &EM = GetContext()->GetEntityManager; // error: reference to non-static member function must be called; Is there a better solution than using a Macro? #define EM GetContext()->GetEntityManager When using an inline function call, i'm afraid, that the compiler will ignore this and i have an unnessessary overhead: inline EntityManager* EM() {

C++ do inline functions prevent copying?

由 自闭症网瘾萝莉.ら 提交于 2019-12-05 21:42:30
Assuming the compiler does in fact inline foo is there a performance difference between these 2 statements? inline int foo (int val) { return val; } int main () { std::cout << foo(123) << std::endl; std::cout << 123 << std::endl; return 0; } Let's ignore any implications that move semantics and copy elision might have. My compiler (gcc 4.7.2) produces nearly identical code for the two statements: _main: LFB1018: pushq %rbx LCFI0: movq __ZSt4cout@GOTPCREL(%rip), %rbx ; std::cout << foo(123) << std::endl; movl $123, %esi movq %rbx, %rdi call __ZNSolsEi movq %rax, %rdi call __ZSt4endlIcSt11char

关于CSS你应该知道的基础知识 - 盒模型篇

由 可紊 提交于 2019-12-05 19:09:57
浏览器渲染引擎通过 盒模型 的方式来布局html元素。我们可以将每一个html元素都看做是一个盒子，每一个盒子都有长和款，多个这样的盒子组成了我们的网页。 Margin，Border，Padding 每一个盒子都会有margin，border和padding属性。我们可以通过CSS来指定这三个属性的大小。例如： .box { margin: 40px; padding: 20px; border: black 2px solid; text-align: center } <body> <div class="box"> box </div> <div class="box"> box </div> <div class="box"> box </div> </body> box class被应用后的样式如下： margin 应用后元素与元素之间产生了相应的空间。 border 应用后元素的外边框增加了宽度。 padding 应用后元素内的内容和边框之间产生了相应的空间。 我们同样可以通过Chrome的Developer Tools来验证相应的属性。上面的代码在Developer Tools中的计算结果如下： 上栗中，我们将盒子四个方向的margin都设置成了40px。我们还可以只修改上下左右中的其中一个或几个。 /* 具体指定上右下左的margin */ .box {

CSS内联--与块级元素区别

由 a 夏天 提交于 2019-12-05 18:56:43
内联元素： 1、内联元素(inline)不会独占一行，相邻的内联元素会排在同一行。其宽度随内容的变化而变化。 2、内联元素不可以设置宽高 3、内联元素可以设置margin，padding，但只在水平方向有效。 块状元素： 1、块级元素会独占一行，默认情况下宽度自动填满其父元素宽度 2、块级元素可以设置宽高 3、块级元素可以设置margin，padding 内联块状元素inline-block： 简单来说就是将对象呈现为inline对象，但是对象的内容作为block对象呈现（可以设置宽高和margin值）。之后的内联对象会被排列在同一内联。比如我们可以给一个link（a元素）inline-block属性值，使其既具有block的宽度高度特性又具有inline的同行特性。 4.互相之间的区别 区别主要是三个方面:一是排列方式，二是宽高边距设置，三是默认宽度。 (1)块级元素会独占一行，而内联元素和内联块元素则会在一行内显示。 (2)块级元素和内联块元素可以设置 width、height 属性，而内联元素设置无效。 (3)块级元素的 width 默认为 100%，而内联元素则是根据其自身的内容或子元素来决定其宽度。 ———————————————— 版权声明：本文为CSDN博主「小奶狗」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。 原文链接

Inlining this function or not?

由 折月煮酒 提交于 2019-12-05 18:43:23
I'm supposed to implement a function which compares two strings simliar so strcmp but ignoring whitespace characters, so strcmpignorews("abc ", " a b c") should give the same result. Here's my implementation: namespace { void SkipWhitespace(const char *&s) { for (; std::isspace(*s, std::locale::classic); ++s); } } int strcmpignorews(const char *s1, const char *s2) { for (; *s1 != '\0' && *s2 != '\0'; ++s1, ++s2) { SkipWhitespace(s1); SkipWhitespace(s2); if (*s1 != *s2) { break; } } return (*s1 < *s2) ? -1 : ((*s1 == *s2) ? 0 : 1); } Now, the question is, would it make sense to inline the

What's the difference in practice between inline and #define?

由 旧时模样 提交于 2019-12-05 18:04:23
问题 As the title says; what's the difference in practice between the inline keyword and the #define preprocessor directive? 回答1: #define is a preprocessor tool and has macro semantics. Consider this, if max(a,b) is a macro defined as #define max(a,b) ((a)>(b)?(a):(b)) : Ex 1: val = max(100, GetBloodSample(BS_LDL)) would spill extra innocent blood, because the function will actually be called twice. This might mean significant performance difference for real applications. Ex 2: val = max(3,

Converting Haskell Polymorphic Cosine function to F#

由 眉间皱痕 提交于 2019-12-05 17:20:18
I'm trying to convert some Haskell code to F# but I'm having some trouble since Haskell is lazy by default and F# is not. I'm also still learning my way around F#. Below is a polymorphic cosine function in Haskell with pretty good performance. I want to try and keep the same or better performance parameters in F#. I would like to see a F# List version and a F# Seq version since the Seq version would be more like the lazy Haskell but the List version would probably perform better. Thanks for any help. Efficiency: number of arithmetic operations used proportional to number of terms in series

inline，宏定义，static，extern

由 梦想与她 提交于 2019-12-05 16:50:17
inline一般用于定义代码简洁，耗时短，不像宏定义是在预编译阶段替换，inline是在汇编阶段替换，效果一样。 一般编译器进行优化的时候会对简短方法进行这种优化，不进行声明也会进行inline，如果显示的声明为inline，会增大最后代码的大小。最终是否优化由编译器决定，这样声明了可以在头文件中定义，不用担心重复定义。 static是告诉链接器，当前文件定义的方法和变量只有当前模块可用，不能被其他的模块使用。 注意，对于 include 方式进行包含的没有影响。 include 实际是对整个文件进行包含。这个一般是对于库与库，或者 .o 与 .o 之间，可见范围由编译器进行分隔。 extern是告诉编译器，如果当前项目没有定义相关的变量， 不需要报错，在链接阶段一定会有相关的定义的。 和static 有些类似，也是使用于模块与模块之间的。 宏定义是在预编译阶段就进行替换。 可以通过 g++ -E source.cpp 的方式查看替换后的代码。 /* [root@localhost definecompile]# g++ -E test.cpp # 1 "test.cpp" # 1 "<built-in>" # 1 "<命令行>" # 1 "/usr/include/stdc-predef.h" 1 3 4 # 1 "<命令行>" 2 # 1 "test.cpp" */ int

Inline div elements

由 此生再无相见时 提交于 2019-12-05 15:37:22
I'm trying to put div elements right next to each other. The problem is, even if there is enough room for the two elements to be on the same line, the new div moves itself to the next line, I need the other div only to go to the next line if there isn't enough room. Does anybody know how to do this? Set the CSS display style to display:inline-block; . This allows the element to keep it's block-like functionality, while also allowing it to be displayed inline. It's a half-way house between the two. (But note that there are some compatibility issues with older versions of IE) Divs are block

Inline MSIL/CIL

由 ￡可爱￡侵袭症＋ 提交于 2019-12-05 14:20:17
I created following simple method: public static void Main () { Console.WriteLine("Hello world!"); Console.ReadKey(true); } Then I used ILSpy to get the MSIL code: .method public hidebysig static void Main() cil managed { .entrypoint .maxstack 8 nop ldstr "Hello world!" call void [mscorlib]System.Console::WriteLine(string) nop ldc.i4.1 call valuetype [mscorlib]System.ConsoleKeyInfo [mscorlib]System.Console::ReadKey(bool) pop ret } Finally I tried to write the MSIL code into my C# code using the #if IL trick that I've found here . public static void Main () { #if IL nop ldstr "Hello world!"
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