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When to use symbols instead of strings in Ruby?
...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are generated dynamically is because of memory concerns.
This question is very common because many programming languages don't h...
List directory in Go
... of everything in the current directory (folders are included but not specially marked - you can check if an item is a folder by using the IsDir() method):
package main
import (
"fmt"
"io/ioutil"
"log"
)
func main() {
files, err := ioutil.ReadDir("./")
if err != nil {
...
Unicode Processing in C++
...use the open source Internation Components for Unicode (ICU) library originally developed by Taligent.
It handles strings, locales, conversions, date/times, collation, transformations, et. al.
Start with the ICU Userguide
...
搭建高可用mongodb集群（二）—— 副本集 - 大数据 & AI - 清泛网 - 专注C/...
...(config);
#输出成功
{
"info" : "Config now saved locally. Should come online in about a minute.",
"ok" : 1
}
#查看日志，副本集启动成功后，138为主节点PRIMARY，136、137为副本节点SECONDARY。
Sun Dec 29 20:26:13.842 [conn3] replSet repl...
JNI converting jstring to char *
...ctions.html
concerning your problem you can use this
JNIEXPORT void JNICALL Java_ClassName_MethodName(JNIEnv *env, jobject obj, jstring javaString)
{
const char *nativeString = env->GetStringUTFChars(javaString, 0);
// use your string
env->ReleaseStringUTFChars(javaString, nat...
How to base64 encode image in linux bash / shell
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
Pass an array of integers to ASP.NET Web API?
...iptor.GetConverter(elementType);
var values = Array.ConvertAll(s.Split(new[] { ","},StringSplitOptions.RemoveEmptyEntries),
x => { return converter.ConvertFromString(x != null ? x.Trim() : x); });
var typedValues = Array.CreateInstance(elementT...
How do I implement __getattribute__ without an infinite recursion error?
I want to override access to one variable in a class, but return all others normally. How do I accomplish this with __getattribute__ ?
...
HTML anchor link - href and onclick both?
...href attribute, I'd return "-1" to prevent the default action, which is usually the browser jumping tot he top of the page, or sometimes I'd just not return anything. Lately I've had to revise all those pages as @Amber advised... to specifically return false, if I don't want the page to jump.
...