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NSUserDefaults - How to tell if a key exists
I'm working on a small iPhone app, and I am using NSUserDefaults as my data persistence. It only has to keep track of a few things, such as some names and some numbers so I figure I might as well keep it simple.
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detect key press in python?
I am making a stopwatch type program in python and I would like to know how to detect if a key is pressed (such as p for pause and s for stop), and I would not like it to be something like raw_input that waits for the user's input before continuing execution. Anyone know how to do this in a while lo...
How does Rails keep track of which migrations have run for a database?
...runs a migration, it takes the leading digits in the migration's file name and inserts a row for that "version", indicating it has been run. If you roll back that migration, Rails will delete the corresponding row from schema_migrations.
For example, running a migration file named 20120620193144_cr...
How is this fibonacci-function memoized?
...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
Th...
Padding is invalid and cannot be removed?
...fic program. I have been using the example provided my msdn for encrypting and decrypting an XmlDocument using the Rijndael algorithm. The encryption works fine but when I try to decrypt, I get the following exception:
...
Convert integer to string Jinja
...egers as strings coming from JSON content files: "hero_title_img_w": "111" and "hero_title_img2_w": "222". Then I'm adding them in .NJK file: {{ hero_title_img_w|int + hero_title_img2_w|int }} to use as image's width attribute. Hope it helps somebody one day.
– revelt
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MySQL “incorrect string value” error when save unicode string in Django
...per here)
To solve this you need to:
Change your MySQL database, table and columns to use the utf8mb4 character set (only available from MySQL 5.5 onwards)
Specify the charset in your Django settings file as below:
settings.py
DATABASES = {
'default': {
'ENGINE':'django.db.backen...
Disable sorting for a particular column in jQuery DataTables
...argets': [ -1 ], for second 'aTargets': [ 1 ], for third 'aTargets': [ 2 ] and so on.
– Lasang
Mar 20 '13 at 7:19
5
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Avoiding memory leaks with Scalaz 7 zipWithIndex/group enumeratees
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....
Handling optional parameters in javascript
...
You can know how many arguments were passed to your function and you can check if your second argument is a function or not:
function getData (id, parameters, callback) {
if (arguments.length == 2) { // if only two arguments were supplied
if (Object.prototype.toString.call(param...