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How to handle Objective-C protocols that contain properties?
...answered May 10 '09 at 5:46
Kendall Helmstetter GelnerKendall Helmstetter Gelner
72.5k2626 gold badges123123 silver badges146146 bronze badges
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Is there an IDictionary implementation that, on missing key, returns the default value instead of th
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Indeed, that won't be efficient at all.
You could always write an extension method:
public static TValue GetValueOrDefault<TKey,TValue>
(this IDictionary<TKey, TValue> dictionary, TKey key)
{
TValue ret;
// Ignore return value
dic...
How to drop all tables in a SQL Server database?
...y tables.
I found that code that works and does everything you try (delete all tables from your database):
DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.C...
TypeError: 'NoneType' object is not iterable in Python
... Correct, But the common scenario author intended here is totally to skip the for loop instead of raising an exception. Python's design is flawed here. When None is treated as an iterable it must return empty list at least. This exception never helped anyone in real life other than m...
Difference between numpy.array shape (R, 1) and (R,)
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1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data bu...
Setting up two different static directories in node.js Express framework
...nal (first) parameter to use() like so:
app.use("/public", express.static(__dirname + "/public"));
app.use("/public2", express.static(__dirname + "/public2"));
That way you get two different directories on the web that mirror your local directories, not one url path that fails over between two lo...
Skip certain tables with mysqldump
...table=schema.table2 > db-data.sql
The resulting two files are structurally sound but the dumped data is now ~500MB rather than 9GB, much better for me. I can now import these two files into another database for testing purposes without having to worry about manipulating 9GB of data or running o...
Purpose of Unions in C and C++
... it for non-overlapping periods of time. These people never meet, and generally don't know anything about each other. By properly managing the time-sharing of the rooms (i.e. by making sure different people don't get assigned to one room at the same time), a relatively small hotel can provide accomm...
How to check for null in Twig?
... Notice: as Twig 2.x check for variable is equal to value like is_ sameas must be {% if var is same as(false) %} not {% if var is sameas(false) %} see Doc url => twig.symfony.com/doc/2.x/tests/sameas.html
– ahmed hamdy
Jul 15 '19 at 17:01
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Convert SVG to image (JPEG, PNG, etc.) in the browser
...out the need for Canvg, which is a pretty large library because it handles all the SVG parsing that an SVG-supporting browser already provides for free. I'm not sure if this satisfies the original use-case, but if so, then see this resource for details.
– Premasagar
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