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How to avoid 'cannot read property of undefined' errors?
...tive "in", but allows paths.
var testObject = {a: {b: {c: 'walrus'}}};
if(_.has(testObject, 'a.b.c')) {
//Safely access your walrus here
}
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Listening for variable changes in JavaScript
...ers): https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects#Defining_getters_and_setters
You can define an object like this, in which aInternal represents the field a:
x = {
aInternal: 10,
aListener: function(val) {},
set a(val) {
this.aInternal = val;
th...
std::unique_lock or std::lock_guard?
...
The difference is that you can lock and unlock a std::unique_lock. std::lock_guard will be locked only once on construction and unlocked on destruction.
So for use case B you definitely need a std::unique_lock for the condition variable. In case A it depends whether you need to relo...
LINQ Join with Multiple Conditions in On Clause
...
Here you go with:
from b in _dbContext.Burden
join bl in _dbContext.BurdenLookups on
new { Organization_Type = b.Organization_Type_ID, Cost_Type = b.Cost_Type_ID } equals
new { Organization_Type = bl.Organization_Type_ID, Cost_Type = bl.Cost_Type_ID }
...
What happened to “HelveticaNeue-Italic” on iOS 7.0.3
...f (font == nil && ([UIFontDescriptor class] != nil)) {
font = (__bridge_transfer UIFont*)CTFontCreateWithName(CFSTR("HelveticaNeue-Italic"), size, NULL);
}
It is also worth noting that in the current version of Xcode (5.0.1 (5A2053)) this font is not listed as an option in the Font dro...
What does “dereferencing” a pointer mean?
...hat can be written to, then you can do things like this:
int x = 2;
int* p_x = &x; // Put the address of the x variable into the pointer p_x
*p_x = 4; // Change the memory at the address in p_x to be 4
assert(x == 4); // Check x is now 4
Above, you must have known at compile time that ...
Capture Image from Camera and Display in Activity
...ass MyCameraActivity extends Activity
{
private static final int CAMERA_REQUEST = 1888;
private ImageView imageView;
private static final int MY_CAMERA_PERMISSION_CODE = 100;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceSta...
Cherry pick using TortoiseGit
...
If you want to cherry pick from one branch to another (for example: Branch_18.1 to Branch_18.4)
Go to Branch_18.4 folder(repo)
Right click and select show log, it will open a log dialog window
In this window, at top left Corner click on Current branch Hyperlink (i.e. Branch_18.4)
Now select the ...
Unresolved Import Issues with PyDev and Eclipse
... "External Libraries". You can add source folders (any folder that has an __init__.py) to the path using that pane. Your project code will then be able to import modules from those source folders.
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Get Android API level of phone currently running my application [duplicate]
...g the API level would be to check the value of android.os.Build.VERSION.SDK_INT, which is an integer.
In either case, the integer you get maps to an enum value from all those defined in android.os.Build.VERSION_CODES:
SDK_INT value Build.VERSION_CODES Human Version Name
1 ...