出于某种原因,我偷偷进入了该类的.NET Framework源代码,Double并发现声明==是:
public static bool operator ==(Double left, Double right) {
return left == right;
}
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每个操作员都适用相同的逻辑.
我尝试在Visual Studio 2005中打开Visual Studio 2008 项目时遇到此错误:
找不到导入的项目"C:\ Microsoft.CSharp.targets".
注意:我不太擅长使用shell.
我试图在Yosemite 上安装Valgrind使用brew.
brew install --HEAD valgrind
接近尾声时,我遇到了与链接有关的错误,所以当我尝试重新安装时,我得到了:
警告:valgrind-HEAD已经安装,它只是没有链接
显然我已经安装了它.然后基于其他SO问题和答案,我试过:
brew link valgrind
这似乎解决了其他人链接已安装的软件的问题,但这给了我一个错误:
Linking /usr/local/Cellar/valgrind/HEAD...
Error: Could not symlink lib/pkgconfig/valgrind.pc
/usr/local/lib/pkgconfig is not writable.
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我也试图更新,brew但它没有解决问题.如果它不可写,也许sudo会给我许可,但我不想在sudo不知道我在做什么的情况下使用.
发生了什么以及如何解决它?
试图在我的机器上安装GeoDjango.我是Python的新手,并被带入一个对其他团队成员来说非常棘手的安装项目.我使用brew安装了Python 2.7和GEOS,并运行了PSQL 9.2.4但是当我尝试运行webserver时仍然遇到此错误:
__import__(name)
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site
packages/django/contrib/gis/geometry/backend/geos.py", line 1, in <module>
from django.contrib.gis.geos import (
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site
packages/django/contrib/gis/geos/__init__.py", line 6, in <module>
from django.contrib.gis.geos.geometry import GEOSGeometry, wkt_regex, hex_regex
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site
packages/django/contrib/gis/geos/geometry.py", line 14, in <module>
from django.contrib.gis.geos.coordseq import GEOSCoordSeq
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site-
packages/django/contrib/gis/geos/coordseq.py", line 9, in <module>
from django.contrib.gis.geos.libgeos import CS_PTR
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site-
packages/django/contrib/gis/geos/libgeos.py", line 119, in <module>
_verinfo = geos_version_info()
File "/Users/armynante/Desktop/uclass-files/uclass-env/lib/python2.7/site
packages/django/contrib/gis/geos/libgeos.py", line 115, in geos_version_info
if not m: raise GEOSException('Could not parse version info string "%s"' % ver) …Run Code Online (Sandbox Code Playgroud) 特别是
我知道如何管理线程等.我很想知道这是否是线程安全的做事方式.
class Program
{
// bogus object
class SomeObject
{
private int value1;
private int value2;
public SomeObject(int value1, int value2)
{
this.value1 = value1;
this.value2 = value2;
}
}
static void Main(string[] args)
{
var s = new SomeObject[10];
var threads = Environment.ProcessorCount - 1;
var stp = new SmartThreadPool(1000, threads, threads);
for (var i = 0; i < 10; i++)
{
stp.QueueWorkItem(CreateElement, s, i);
}
}
static void CreateElement(SomeObject[] s, int index)
{ …Run Code Online (Sandbox Code Playgroud) 我想做这样的事情:
$ [mysql query that produces many lines] | php parse_STDIN.php
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在parse_STDIN.php文件中我希望能够从stdin逐行解析我的数据.
我已经通过网络问了几个关于这个问题的问题,但我没有找到任何问题的答案,或者它是针对另一种语言的,或者它没有完全回答(死代码不是无用的代码)所以这是我的问题:
编译器是否忽略(显式或非显式)无用代码?
例如,在此代码中:
double[] TestRunTime = SomeFunctionThatReturnDoubles;
// A bit of code skipped
int i = 0;
for (int j = 0; j < TestRunTime.Length; j++)
{
}
double prevSpec_OilCons = 0;
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for循环会被删除吗?
背景是我维护了很多代码(我没有写),我想知道无用的代码是否应该是目标,或者我是否可以让编译器处理它.
我正在定义一个文件组件
我想在该组件上使用props选项.
但是我在哪里可以添加代码?
<template>
<div class="hello">
<h1>{{ msg }}</h1>
</div>
</template>
<script>
export default {
data () {
return {
// note: changing this line won't causes changes
// with hot-reload because the reloaded component
// preserves its current state and we are modifying
// its initial state.
msg: 'Hello World!'
}
}
}
</script>
<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
h1 {
color: #42b983;
}
</style>
Run Code Online (Sandbox Code Playgroud) 尽管进行了一些搜索,但我还是找不到使用QT Creator 2.3.1自动生成C++类的getter和setter的方法.你们知道某种方法吗?
//save tablet
jQuery("#savetablet"+jTablets[i].idtablets).on('click', function()
{
alert("alertsepy2...");
console.log(jTablets[i].idtablets);
jQuery("#tablet"+jTablets[i].idtablets+" .detailsrow").each(function( index ) {
$(this).each(function( index2 ) {
console.log($(this).html());
});
});
});
<div class="column0"><input type="text" value="-D"></div>
<div class="column1"><input type="text" value="D"></div>
<div class="column2"><input type="text" value="D"></div>
<div class="column3"><input type="number" value="0"></div>
<div class="column4"> <input type="number" value="0"></div>
<div class="column5"> <input type="number" value="0"></div>
<div class="column6"><input type="number" value="0"></div>
<div class="column7"><input type="number" value="0"></div>
<div class="column8"><input type="number" value="0"></div>
<div class="column9"> <input type="number" value="0"></div>
<div class="column10"> <input type="number" value=""></div>
<div id="tablet17row0" class="column11">11</div>
<div class="column0"><input type="text" value="-D"></div>
<div class="column1"><input type="text" value="D"></div>
<div …Run Code Online (Sandbox Code Playgroud)