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file_put_contents(meta/services.json): failed to open stream: Permission denied
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edited Nov 5 '18 at 19:43
answered Jun 23 '14 at 15:17
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Why can I throw null in Java? [duplicate]
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It looks like it's not that null is treated as a NullPointerException, but that the act of attempting to throw null itself throws a NullPointerException.
In other words, throw checks that its argument is nonnull, and if it...
Is there any way to ignore INSTALL_FAILED_VERSION_DOWNGRADE on application install with the Android
It seems like the most recent Android 4.2 has introduced this error condition on installation when one attempts to install an APK with a lower version. In prior versions of Android, one would be able to install older APK's simply via adb install -r <link to APK> . For debugging purposes, I f...
Can table columns with a Foreign Key be NULL?
...the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE child (id INT NULL,
parent_id INT NULL,
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What is the difference between a “function” and a “procedure”?
...nd a procedure just executes commands.
The name function comes from math. It is used to calculate a value based on input.
A procedure is a set of command which can be executed in order.
In most programming languages, even functions can have a set of commands. Hence the difference is only in the r...
How to Correctly handle Weak Self in Swift Blocks with Arguments
...k self].
If self will never be nil in the closure use [unowned self].
If it's crashing when you use [unowned self] I would guess that self is nil at some point in that closure, which is why you had to go with [weak self] instead.
I really liked the whole section from the manual on using strong, ...
Resizing UITableView to fit content
...ave a question in a UILabel and a multiple choice answers displayed in UITableView , each row showing a multiple choice. Questions and answers will vary, so I need this UITableView to be dynamic in height.
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How do I change selected value of select2 dropdown with JqGrid?
I'm using Oleg's select2 demo , but I am wondering whether it would be possible to change the currently selected value in the dropdown menu.
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What is a “translation unit” in C++
I am reading at the time the "Effective C++" written by Meyers
and came across the term "translation unit".
11 Answers
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Filter dataframe rows if value in column is in a set list of values [duplicate]
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edited Feb 25 at 0:45
Harvey
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