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What is the difference between a weak reference and an unowned reference?
...nefit).
A weak reference allows the possibility of it to become nil (this happens automatically when the referenced object is deallocated), therefore the type of your property must be optional - so you, as a programmer, are obligated to check it before you use it (basically the compiler forces you, ...
Getting the current Fragment instance in the viewpager
... @Maarten No, it's just a common hack that has been used since the adapter appeared(and its source code was available), it hasn't changed yet. If you want something more reliable you'll need to use other options, most notable overriding the instantiateItem() method and getting references to the prop...
Losing scope when using ng-include
...ll be lost and I will have a constant 0.00 value on the view div while the app is running.
– zahra
Mar 31 '16 at 4:53
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Why use getters and setters/accessors?
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I'm sitting and staring at a 500k line app where it's never been needed. That said, if it's needed once, it'd start causing a maintenance nightmare. Good enough for a checkmark for me.
– Dean J
Oct 14 '09 at 18:24
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Text Progress Bar in the Console [closed]
I wrote a simple console app to upload and download files from an FTP server using the ftplib.
31 Answers
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List all sequences in a Postgres db 8.1 with SQL
...The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the following query:
SELECT last_value FROM...
How to create a file in memory for user to download, but not through server?
... URIs. Browser support varies; see Wikipedia. Example:
<a href="data:application/octet-stream;charset=utf-16le;base64,//5mAG8AbwAgAGIAYQByAAoA">text file</a>
The octet-stream is to force a download prompt. Otherwise, it will probably open in the browser.
For CSV, you can use:
<...
Why modelVersion of pom.xml is necessary and always set to 4.0.0?
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LOL my app was on version 4 and I got an error while updating the version to 5!
– Chloe
Dec 14 '18 at 23:05
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Do AJAX requests retain PHP Session info?
If I had a user logged onto my site, having his id stored in $_SESSION , and from his browser he clicked a 'Save' button which would make an AJAX request to the server. Will his $_SESSION and cookies be retained in this request, and can I safely rely on the id being present in the $_SESSION ?
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What is the difference between an expression and a statement in Python?
...xpressions as expression statements, e.g. print("Hello world!") or my_list.append(42).
– Sven Marnach
May 28 '19 at 12:09
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