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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
... in Visual Studio 2017 see the end of this answer)
Consider this code:
String s = null;
Console.WriteLine(s.Length);
This will throw a NullReferenceException in the second line and you want to know why .NET doesn't tell you that it was s that was null when the exception was thrown.
To underst...
returning a Void object
...<T> action) {
return action.execute();
}
you can call it like
String result = executeAction(new Action<String>() {
@Override
public String execute() {
//code here
return "Return me!";
}
});
or, for the void action (note that you're not assigning the r...
Why does the JVM still not support tail-call optimization?
....
Consider the following program:
public class Test {
public static String f() {
String s = Math.random() > .5 ? f() : g();
return s;
}
public static String g() {
if (Math.random() > .9) {
StackTraceElement[] ste = new Throwable().getStackTra...
How can I get form data with JavaScript/jQuery?
...s something that returns an array with key-value pairs instead of a single string?
– Bart van Heukelom
Feb 16 '10 at 21:28
83
...
Convert floats to ints in Pandas?
...ll edit all the floats, so it may be better to convert your FK column to a string, do the manipulation, and then save.
– Ryan G
Jan 22 '14 at 19:30
...
Java resource as file
... a File object
File dir = new File(dir_url.toURI());
// List the directory
String files = dir.list()
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Where is the documentation for the values() method of Enum?
...
* Returns the enum constant of this type with the specified
* name.
* The string must match exactly an identifier used to declare
* an enum constant in this type. (Extraneous whitespace
* characters are not permitted.)
*
* @return the enum constant with the specified name
* @throws IllegalArgume...
Use of 'use utf8;' gives me 'Wide character in print'
...
Without use utf8 Perl interprets your string as a sequence of single byte characters. There are four bytes in your string as you can see from this:
$ perl -E 'say join ":", map { ord } split //, "鸡\n";'
233:184:161:10
The first three bytes make up your chara...
Regular expression to match DNS hostname or IP Address?
...
yes to valid a string start ^ and end $ are required, but if you are searching an IP into a text do not use it.
– Alban
Nov 28 '13 at 15:04
...
How to split a file into equal parts, without breaking individual lines? [duplicate]
...
var dict = File.ReadLines("test.txt")
.Where(line => !string.IsNullOrWhitespace(line))
.Select(line => line.Split(new char[] { '=' }, 2, 0))
.ToDictionary(parts => parts[0], parts => parts[1]);
or
enter code here
line="to=xxx@gmail...