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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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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 ...
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...
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 ...
How to profile a bash shell script slow startup?
...
PS4='+ $EPOCHREALTIME\011 '
As pointed out by @pawamoy, you can use BASH_XTRACEFD to send the output of the trace to a separate file descriptor if you have Bash 4.1 or later. From this answer:
#!/bin/bash
exec 5> command.txt
BASH_XTRACEFD="5"
echo -n "hello "
set -x
echo -n world
set +x
e...
Why would a JavaScript variable start with a dollar sign? [duplicate]
...; // refers to the jQuery object representation of the dom object
var email_field = $("#email").get(0); // refers to the dom object itself
I find this to be very helpful in writing jQuery code and makes it easy to see jQuery objects which have a different set of properties.
...
TypeScript sorting an array
..., b) {
var ax = [], bx = [];
a.replace(/(\d+)|(\D+)/g, function (_, $1, $2) { ax.push([$1 || Infinity, $2 || ""]) });
b.replace(/(\d+)|(\D+)/g, function (_, $1, $2) { bx.push([$1 || Infinity, $2 || ""]) });
while (ax.length && bx.length) {
var an = ax.shift();
...