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Return type of '?:' (ternary conditional operator)
...alue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues and prvalues.)
In very broad and simple terms, an lvalue refers to an object in memory and an rvalue is just a value that may not necessarily be attached to an object in memory.
An...
SQLite - UPSERT *not* INSERT or REPLACE
...ddition to INSERT that causes the INSERT to behave as an UPDATE or a no-op if the INSERT would violate a uniqueness constraint. UPSERT is not standard SQL. UPSERT in SQLite follows the syntax established by PostgreSQL.
GOOD but tendous: This will update 2 of the columns.
When ID=1 exists, the NA...
Delete all but the most recent X files in bash
...d globbing.
inability to distinguish between files and directories (i.e., if directories happened to be among the 5 most recently modified filesystem items, you'd effectively retain fewer than 5 files, and applying rm to directories will fail).
wnoise's answer addresses these issues, but the solu...
Check if current directory is a Git repository
...rg.uk/).
# Distributed under the GNU General Public License, version 2.0.
if [ -d .git ]; then
echo .git;
else
git rev-parse --git-dir 2> /dev/null;
fi;
You could either wrap that in a function or use it in a script.
Condensed into a one line condition suitable for bash and zsh
[ -d .git...
I want to remove double quotes from a String
...console.log(someStr.replace(/['"]+/g, ''));
That should do the trick... (if your goal is to replace all double quotes).
Here's how it works:
['"] is a character class, matches both single and double quotes. you can replace this with " to only match double quotes.
+: one or more quotes, chars, a...
How to do if-else in Thymeleaf?
What's the best way to do a simple if - else in Thymeleaf?
10 Answers
10
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How to detect the currently pressed key?
...
if ((Control.ModifierKeys & Keys.Shift) != 0)
This will also be true if Ctrl+Shift is down. If you want to check whether Shift alone is pressed,
if (Control.ModifierKeys == Keys.Shift)
If you're in a class that inh...
Check if a string contains one of 10 characters
I'm using C# and I want to check if a string contains one of ten characters, *, &, # etc etc.
6 Answers
...
Find an element in a list of tuples
...
If you just want the first number to match you can do it like this:
[item for item in a if item[0] == 1]
If you are just searching for tuples with 1 in them:
[item for item in a if 1 in item]
...
How does Dijkstra's Algorithm and A-Star compare?
...f each node is calculated by f(x)=g(x)+h(x)
A* search only expands a node if it seems promising. It only focuses to reach the goal node from the current node, not to reach every other nodes. It is optimal, if the heuristic function is admissible.
So if your heuristic function is good to approximat...