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How do I concatenate two arrays in C#?
...rays. It seems the only functional purpose for using arrays is for Interop calls (Unmanaged C++).
– Levi Fuller
Oct 26 '15 at 22:40
1
...
Mechanisms for tracking DB schema changes [closed]
...change you make to the database, you write a new migration. Migrations typically have two methods: an "up" method in which the changes are applied and a "down" method in which the changes are undone. A single command brings the database up to date, and can also be used to bring the database to a spe...
What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?
... A subtle difference is:- ?: can improve performance in recursive called makefiles. For e.g if $? = $(shell some_command_that_runs_long_time). In recursive calls this will be evaluated only once. causing gains in build performance. := will be slower since the command is needlessly running m...
Best way to clear a PHP array's values
...
Like Zack said in the comments below you are able to simply re-instantiate it using
$foo = array(); // $foo is still here
If you want something more powerful use unset since it also will clear $foo from the symbol table, if you need ...
CodeIgniter: Create new helper?
... return $var;
}
}
Save this to application/helpers/ . We shall call it "new_helper.php"
The first line exists to make sure the file cannot be included and ran from outside the CodeIgniter scope. Everything after this is self explanatory.
Using the Helper
This can be in your controll...
How can I get the behavior of GNU's readlink -f on a Mac?
...e. Obviously you could insert this in your own script where you'd like to call readlink -f
#!/bin/sh
TARGET_FILE=$1
cd `dirname $TARGET_FILE`
TARGET_FILE=`basename $TARGET_FILE`
# Iterate down a (possible) chain of symlinks
while [ -L "$TARGET_FILE" ]
do
TARGET_FILE=`readlink $TARGET_FILE`...
How to insert a row in an HTML table body in JavaScript
...t a reference to it and add it there.
var tableRef = document.getElementById('myTable').getElementsByTagName('tbody')[0];
// Insert a row in the table at the last row
var newRow = tableRef.insertRow();
// Insert a cell in the row at index 0
var newCell = newRow.insertCell(0);
// Append a text...
How to write loop in a Makefile?
...This is good if you have 4 CPUs say, and a good test of any makefile.
Basically, you want make to see something like:
.PHONY: all
all: job1 job2 job3
.PHONY: job1
job1: ; ./a.out 1
.PHONY: job2
job2: ; ./a.out 2
.PHONY: job3
job3: ; ./a.out 3
This is -j friendly (a good sign). Can you spot th...
Amazon Interview Question: Design an OO parking lot [closed]
...ss.
ParkingSpace has an Entrance.
Entrance has a location or more specifically, distance from Entrance.
ParkingLotSign is a class.
ParkingLot has a ParkingLotSign.
ParkingLot has a finite number of ParkingSpaces.
HandicappedParkingSpace is a subclass of ParkingSpace.
RegularParkingSpace is a ...
Java 8 NullPointerException in Collectors.toMap
... This might be quite slow on a large input. You create a HashMap and then call putAll() for every single entry. Personally, at given circumstances, I would go with non-stream solution, or forEach() if the input is parallel.
– Ondra Žižka
Nov 30 '18 at 14:06
...