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?: operator (the 'Elvis operator') in PHP
... left operand is truthy, and the right operand otherwise.
In pseudocode,
foo = bar ?: baz;
roughly resolves to
foo = bar ? bar : baz;
or
if (bar) {
foo = bar;
} else {
foo = baz;
}
with the difference that bar will only be evaluated once.
You can also use this to do a "self-check"...
What is the correct way to check for string equality in JavaScript?
...= operator can have very unexpected results due to the type-coercion internally, so using === is always the recommended approach.
For insight into this, and other "good vs. bad" parts of Javascript read up on Mr. Douglas Crockford and his work. There's a great Google Tech Talk where he summarizes ...
Passing just a type as a parameter in C#
...ic T GetColumnValue<T>(this string columnName){...} then you can say foo.GetColumnValues<string>(dm.mainColumn)
– Joshua G
Jun 4 '14 at 15:56
...
Mac OSX Lion DNS lookup order [closed]
... that file very light.
One advantage of running something like dnsmasq locally (besides the significant performance boost) is that you can redirect whole top-level domains back to your local machine. This allows you to have the whole *.dev namespace for development (for instance), without having to...
How do I increase the number of displayed lines of a Java stack trace dump?
...stack trace will be shortened. If you for some reason want the full trace, all you need to do is take the last line before the ... in Foo's stack trace and look for it in the Bar's stack trace; everything below that line is exactly what would have been printed in Foo's stack trace.
...
What's the difference between git clone --mirror and git clone --bare
...
The difference is that when using --mirror, all refs are copied as-is. This means everything: remote-tracking branches, notes, refs/originals/* (backups from filter-branch). The cloned repo has it all. It's also set up so that a remote update will re-fetch everything f...
Checking for NULL pointer in C/C++ [closed]
In a recent code review, a contributor is trying to enforce that all NULL checks on pointers be performed in the following manner:
...
Are PostgreSQL column names case-sensitive?
...
All identifiers (including column names) that are not double-quoted are folded to lower case in PostgreSQL. Column names that were created with double-quotes and thereby retained upper-case letters (and/or other syntax violat...
How do I get the file extension of a file in Java?
...
Do you really need a "parser" for this?
String extension = "";
int i = fileName.lastIndexOf('.');
if (i > 0) {
extension = fileName.substring(i+1);
}
Assuming that you're dealing with simple Windows-like file names, not som...
Difference between / and /* in servlet mapping url pattern
...
<url-pattern>/*</url-pattern>
The /* on a servlet overrides all other servlets, including all servlets provided by the servletcontainer such as the default servlet and the JSP servlet. Whatever request you fire, it will end up in that servlet. This is thus a bad URL pattern for servle...