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What does an exclamation mark mean in the Swift language?
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OK. So the docs talk about using ! when you know for sure it can be unwrapped. But you can run the code fine without it (a forth option for your list - implicit unwrapping) AND without checking first. You get back the value or nil if nil. But if you know for sure that ...
What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL...
Split a python list into other “sublists” i.e smaller lists [duplicate]
...tually it is equivalent, except for a bug where the last batch is missing, now fixed.
– qris
Sep 1 '15 at 8:54
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How to set auto increment primary key in PostgreSQL?
...plog_adfarm_seq'),
'Will the smart cookies catch the crumb? Find out now!'
);
Step 4, observe the rows
el@defiant ~ $ psql -U pgadmin -d kurz_prod -c "select * from splog_adfarm"
splog_key | splog_value
----------+--------------------...
How do you delete a column by name in data.table?
...hough data.table is gradually moving away from using this argument so it's now discouraged where you can avoid it; showing here so you know the option exists in case you really do need it:
# Method 5a (like Method 3)
df3[, !"foo", with=FALSE]
# Method 5b (like Method 4)
df3[, !grep("^foo$", names(...
Can you disable tabs in Bootstrap?
...Thanks worked a treat, also added css "cursor:no-drop;" for cursor so use knows why they can't click it
– arbme
Feb 11 '12 at 3:11
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What is a Portable Class Library?
... run on a variety of .NET-based platforms without recompilation.
MSDN now has a nice article/documentation on it. You can check it out and see what is supported in Portable Class Library .
The following assemblies are available within a Portable Class Library project:
mscorlib.dl...
Which characters are valid in CSS class names/selectors?
What characters/symbols are allowed within the CSS class selectors?
I know that the following characters are invalid , but what characters are valid ?
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How to create a self-signed certificate for a domain name for development?
...xactly. This is wrong! "Friendly name" has nothing to do with CN. I don't know why this answer has so many upvotes?
– c00000fd
Sep 23 '15 at 20:41
25
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What are best practices for using SmtpClient, SendAsync and Dispose under .NET 4.0
I'm a bit perplexed on how to manage SmtpClient now that it is disposable, especially if I make calls using SendAsync. Presumably I should not call Dispose until SendAsync completes. But should I ever call it (e.g., using "using"). The scenario is a WCF service which mails out email periodically ...