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General suggestions for debugging in R
...the debug() function and step through the script line by line.
The best new trick in R 2.10 (when working with script files) is to use the findLineNum() and setBreakpoint() functions.
As a final comment: depending upon the error, it is also very helpful to set try() or tryCatch() statements ar...
What is “callback hell” and how and why does RX solve it?
...g state variables. I found RX was the cleanest implementation to perform a new network request after 3 network responses returned or to error handle the whole chain if one does not return. Then it can reset itself and wait for the same 3 events.
– colintheshots
...
Javascript : Send JSON Object with Ajax?
....stringify({name:"John", time:"2pm"}) });
Without jQuery:
var xmlhttp = new XMLHttpRequest(); // new HttpRequest instance
xmlhttp.open("POST", "/json-handler");
xmlhttp.setRequestHeader("Content-Type", "application/json");
xmlhttp.send(JSON.stringify({name:"John Rambo", time:"2pm"}));
...
Strip all non-numeric characters from string in JavaScript
...example
– max4ever
Oct 23 '14 at 12:51
2
Not good: "aaa 2.9px of bbb.".replace(/[^\d.-]/g, '') ...
Add a reference column migration in Rails 4
...ails 4.x
When you already have users and uploads tables and wish to add a new relationship between them.
All you need to do is: just generate a migration using the following command:
rails g migration AddUserToUploads user:references
Which will create a migration file as:
class AddUserToUpload...
Android ViewPager with bottom dots
... You want to use com.google.android.material.tabs.TabLayout in newer Versions
– schlenger
Mar 7 '19 at 15:50
2
...
Clearing a string buffer/builder after loop
...
One option is to use the delete method as follows:
StringBuffer sb = new StringBuffer();
for (int n = 0; n < 10; n++) {
sb.append("a");
// This will clear the buffer
sb.delete(0, sb.length());
}
Another option (bit cleaner) uses setLength(int len):
sb.setLength(0);
See Javado...
JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
15
...
How to change the timeout on a .NET WebClient object
...ivate string GetRequest(string aURL)
{
using (var lWebClient = new WebClient())
{
lWebClient.Timeout = 600 * 60 * 1000;
return lWebClient.DownloadString(aURL);
}
}
sha...
How do I run a simple bit of code in a new thread?
...te your own thread, this is as simple as it gets:
using System.Threading;
new Thread(() =>
{
Thread.CurrentThread.IsBackground = true;
/* run your code here */
Console.WriteLine("Hello, world");
}).Start();
...