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Capture Image from Camera and Display in Activity
...ntents/result#kotlin
There are many built-in ActivityResultContracts that allow you to do different things like pick contacts, request permissions, take pictures or take videos. You are probably interested in the ActivityResultContracts.TakePicture shown above.
Note that androidx.fragment 1.3.0-al...
How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
How do you detect/avoid Memory leaks in your (Unmanaged) code? [closed]
... Valgrind for Linux (and OS X). If you use windose - deleaker - best of all!
– John Smith
Dec 12 '11 at 18:12
...
How can I cast int to enum?
... (e.g. "2342342" -- assuming that's not a value of your enum), it will actually allow that without throwing an error! Your enum will have that value (2342342) even though it's not a valid choice in the enum itself.
– JoeCool
Jun 25 '13 at 15:14
...
How can I append a string to an existing field in MySQL?
I want to update the code on all my record to what they currently are plus _standard any ideas?
2 Answers
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What is the difference between typeof and instanceof and when should one be used vs. the other?
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@Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Colin D
...
String formatting in Python 3
...format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)
"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)
"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) ...
How to slice an array in Bash
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There is also a convenient shortcut to get all elements of the array starting with specified index. For example "${A[@]:1}" would be the "tail" of the array, that is the array without its first element.
version=4.7.1
A=( ${version//\./ } )
echo "${A[@]}" # 4 7 1
B...
Is there a standard sign function (signum, sgn) in C/C++?
...T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or T) rather than an int, which seems wasteful.
Works ...
How is null + true a string?
...t's walk through this in turn.
X is the null type here - or not a type at all, if you want to think of it that way. It's not providing any candidates. Y is bool, which doesn't provide any user-defined + operators. So the first step finds no user-defined operators.
The compiler then moves on to the...