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Does ARC support dispatch queues?
...
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage them.
If your deployment target is iOS 6.0 or Mac OS X 10.8 or later
ARC will manage your queue for you. Yo...
Git Alias - Multiple Commands and Parameters
...performing redirections and return the status 0. Here're some usages: 1. a=123;$a errors, but a=123; : $a does not. 2. : > hello.txt empties hello.txt. 3. if [ "$a" = "hello" ];then : ;fi runs okay but errors without ':'. It's like pass in python. 4. : this is a comment, the colon followed by spa...
How to run a program without an operating system?
...ill only load a small block of code.
Many ARM boards let you do some of those things. Some have boot loaders to help you with basic setup.
Here you may find a great tutorial on how to do a basic operating system on a Raspberry Pi.
Edit:
This article, and the whole wiki.osdev.org will anwer most o...
Why do == comparisons with Integer.valueOf(String) give different results for 127 and 128?
...th that in mind, consider the difference between these three.
new Integer(123);
This (obviously) makes a brand new Integer object.
Integer.parseInt("123");
This returns an int primitive value after parsing the String.
Integer.valueOf("123");
This is more complex than the others. It starts ...
Get loop counter/index using for…of syntax in JavaScript
... both the value and the index to the function you give it:
var myArray = [123, 15, 187, 32];
myArray.forEach(function (value, i) {
console.log('%d: %s', i, value);
});
// Outputs:
// 0: 123
// 1: 15
// 2: 187
// 3: 32
Or ES6’s Array.prototype.entries, which now has support across current ...
JavaScript style for optional callbacks
...swered Mar 31 '14 at 11:16
ninja123ninja123
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Multiline comment in PowerShell
...red Sep 2 '18 at 18:32
ÜberUser123ÜberUser123
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Iterating through directories with Python
...with a simple print statement you can see that each file is found:
import os
rootdir = 'C:/Users/sid/Desktop/test'
for subdir, dirs, files in os.walk(rootdir):
for file in files:
print os.path.join(subdir, file)
If you still get errors when running the above, please provide the error...
Export query result to .csv file in SQL Server 2008
...out add the querytimeout so e.g. Invoke-Sqlcmd -ServerInstance MySQLserver123 -Query $QueryFmt -querytimeout 600 | Export-CSV $AttachmentPath
– Tilo
Apr 6 '17 at 16:44
1
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Adding :default => true to boolean in existing Rails column
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change_column :things, :price_1, :integer, default: 123, null: false
Seems to be best way to add a default to an existing column that doesn't have null: false already.
Otherwise:
change_column :things, :price_1, :integer, default: 123
Some research I did on this:
https:...