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How do I remove a property from a JavaScript object?
...perties from objects.
For arrays, deleting a property corresponding to an index, creates a sparse array (ie. an array with a "hole" in it). Most browsers represent these missing array indices as "empty".
var array = [0, 1, 2, 3]
delete array[2] // [0, 1, empty, 3]
Note that delete does not reloc...
How to get first character of string?
...
x.charAt() will also return the first character as if no index is passed to this method, it will assume it to the 0.
– Mohammad Usman
Jan 4 '18 at 12:05
1
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Why is it slower to iterate over a small string than a small list?
...unobvious, but is likely created from a greater number of checks on string indexing, with regards to the type and well-formedness. It is also quite likely thanks to the need to check what to return.
List indexing is remarkably fast.
>>> python3 -m timeit '[x for x in "abc"]'
1000000 l...
jQuery Mobile: document ready vs. page events
...tead of document selector. Let's say we have jQuery Mobile page with an id index:
<div data-role="page" id="index">
<div data-theme="a" data-role="header">
<h3>
First Page
</h3>
<a href="#second" class="ui-btn-right">Next</a&g...
How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...you had was related to column usage. Column could be used in a constraint, index or another calculated column.
– Alex Aza
Jun 14 '11 at 15:43
...
Remove duplicate rows in MySQL
...
A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
This will drop all the duplicate rows. As an ...
What does enumerate() mean?
...rt, it loops over the elements of an iterable (like a list), as well as an index number, combined in a tuple:
for item in enumerate(["a", "b", "c"]):
print item
prints
(0, "a")
(1, "b")
(2, "c")
It's helpful if you want to loop over a sequence (or other iterable thing), and also want to ha...
How to raise a ValueError?
I have this code which finds the largest index of a specific character in a string, however I would like it to raise a ValueError when the specified character does not occur in a string.
...
Handling click events on a drawable within an EditText
...presents the left drawable.
* */
public static final int DRAWABLE_INDEX_LEFT = 0;
/**
* This represents the top drawable.
* */
public static final int DRAWABLE_INDEX_TOP = 1;
/**
* This represents the right drawable.
* */
public static final int DRAWABLE_...
How to fix HTTP 404 on Github Pages?
...Hub repository on the gh-pages branch.
Everything looks good, I have my index.html , my CSS, JS and pictures folders.
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