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delete a.x vs a.x = undefined
...a.x = undefined
means that a.hasOwnProperty("x") will still return true, and therefore, it will still show up in a for in loop, and in Object.keys()
delete a.x
means that a.hasOwnProperty("x") will return false
The way that they are the same is that you can't tell if a property exists by testi...
How do you disable viewport zooming on Mobile Safari?
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This is a rather old answer and coming to the problem I had read that if you set user-scalable to no this would cause accessibility problems. As of iOS 10 it works fine, allowing the user to zoom if he wishes, but but not zooming the input box otherwise...
What is the proper way to format a multi-line dict in Python?
...uld use a similar but not identical format as your format 3. Here is mine, and why.
my_dictionary = { # Don't think dict(...) notation has more readability
"key1": 1, # Indent by one press of TAB (i.e. 4 spaces)
"key2": 2, # Same indentation scale as above
"key3": 3, # Keep this final c...
MD5 algorithm in Objective-C
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md5 is available on the iPhone and can be added as an addition for ie NSString and NSData like below.
MyAdditions.h
@interface NSString (MyAdditions)
- (NSString *)md5;
@end
@interface NSData (MyAdditions)
- (NSString*)md5;
@end
MyAdditions.m
#import...
Disabling and enabling a html input button
... jquery 1.6.1 changes. As a suggestion, always use the latest jquery files and the prop() method.
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Disable submit button when form invalid with AngularJS
...form/> tag, if for no other reason than it allows a user to hit [ENTER] and submit the form. But it also likely constitutes better practice because of things like accessibility concerns.
– Ben Lesh
Nov 13 '14 at 20:14
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How to use Checkbox inside Select Option
...e select element but you can get the same functionality by using HTML, CSS and JavaScript. Here is a possible working solution. The explanation follows.
Code:
var expanded = false;
function showCheckboxes() {
var checkboxes = document.getElementById("checkboxes");
if (!expanded) {...
Python Pandas Error tokenizing data
I'm trying to use pandas to manipulate a .csv file but I get this error:
39 Answers
39...
Python - write() versus writelines() and concatenated strings
So I'm learning Python. I am going through the lessons and ran into a problem where I had to condense a great many target.write() into a single write() , while having a "\n" between each user input variable(the object of write() ).
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Test whether a list contains a specific value in Clojure
...se for sets (which can be thought of as making no distinction between keys and values), maps (so (contains? {:foo 1} :foo) is true) and vectors (but note that (contains? [:foo :bar] 0) is true, because the keys here are indices and the vector in question does "contain" the index 0!).
To add to the ...