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How to check for null in Twig?
...NULL, and not any other value that evaluates to false (such as zero, empty string and empty array). Besides, it will cause an error if var is not defined. A safer way would be:
{% if var is not defined or var is null %}
which can be shortened to:
{% if var|default is null %}
If you don't provi...
Save An Image To Application Documents Folder From UIView On IOS
...thForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
NSString *filePath = [documentsPath stringByAppendingPathComponent:@"image.png"]; //Add the file name
[pngData writeToFile:filePath atomically:YES]; /...
Is there a difference between x++ and ++x in java?
...you javac this Y.java class:
public class Y {
public static void main(String []args) {
int y = 2;
y = y++;
}
}
and javap -c Y, you get the following jvm code (I have allowed me to comment the main method with the help of the Java Virtual Machine Specification):
public cla...
JavaScript get clipboard data on paste event (Cross browser)
... cycle through the pasted content using normal dom methods, or get it as a string using innerHTML. You can then restore the previous contents of the div, and insert whatever content you like. Oh, and you have to use the same timer hack as above. I'm surprised TinyMCE doesn't do this...
...
Are HTML comments inside script tags a best practice? [closed]
... page :
Commenting scripts in JavaScript The JavaScript engine allows the string "<!--" to occur at the start of a SCRIPT element, and ignores further characters until the end of the line. JavaScript interprets "//" as starting a comment extending to the end of the current line. This is needed t...
What's the role of adapters in Android?
...}
void manyMoreMethods(){}
}
Lets define an adapter:
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, values);
First parameter: Context
Second parameter: Layout for the row
Third parameter: ID of the TextVi...
Logical Operators, || or OR?
...s a boolean. If it returns a value PHP considers truthy (true, a non-empty string, etc.), it will not call die().
– Matthew Ratzloff
Nov 1 '13 at 17:20
...
How does HashSet compare elements for equality?
...c class Employe
{
public Employe() {
}
public string Name { get; set; }
public override string ToString() {
return Name;
}
public override bool Equals(object obj) {
return this.Name.Equals(((Employe)obj).Name);
}...
What is a sealed trait?
...ealed trait is
JSON.
A JSON value can only be JSON null, boolean, number, string, array, or dictionary.
JSON has not changed in 20 years, so it is unlikely that anyone will need to extend our JSON
with additional subclasses.
While the set of sub-classes is fixed, the range of operations we may want...
Calling closure assigned to object property directly
...t;__invoke();
Of course that won't work if the callback is an array or a string (which can also be valid callbacks in PHP) - just for closures and other objects with __invoke behavior.
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