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Deleting Objects in JavaScript
... of them would cause a crash. To make them all turn null would mean having extra work when deleting or extra memory for each object.)
Since Javascript is garbage collected, you don't need to delete objects themselves - they will be removed when there is no way to refer to them anymore.
It can be ...
How to print an exception in Python?
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In case you want to pass error strings, here is an example from Errors and Exceptions (Python 2.6)
>>> try:
... raise Exception('spam', 'eggs')
... except Exception as inst:
... print type(inst) # the exception instance
... print ins...
How can I use map and receive an index as well in Scala?
...ted
scala> ci map (i => i+"=#"+ci.count) toList
res0: List[java.lang.String] = List(These=#0,are=#1,words=#2)
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Best practices for circular shift (rotate) operations in C++
...n-circular shifts work on that target.
Current x86 compilers still use an extra instruction to mask a variable count for 8 and 16-bit rotates, probably for the same reason they don't avoid the AND on ARM. This is a missed optimization, because performance doesn't depend on the rotate count on any ...
How to tell if a tag failed to load
...ISS IMHO).
From the spec:
If the src attribute's value is the
empty string or if it could not be
resolved, then the user agent must
queue a task to fire a simple event
named error at the element, and
abort these steps.
~
If the load resulted in an error (for
example a DNS erro...
What are the differences between the threading and multiprocessing modules?
...at the same speed. (In reality, it'll run a little slower, because there's extra overhead from threading, even if you don't have any shared data, but ignore that for now.)
There are exceptions to this. If your code's heavy computation doesn't actually happen in Python, but in some library with cust...
Rails 4 multiple image or file upload using carrierwave
...ploader Avatar
Create post scaffold
rails generate scaffold post title:string
Create post_attachment scaffold
rails generate scaffold post_attachment post_id:integer avatar:string
rake db:migrate
In post.rb
class Post < ActiveRecord::Base
has_many :post_attachments
accepts_nested...
How can I export tables to Excel from a webpage [closed]
...possible to use the old Excel 2003 XML format (before OpenXML) to create a string that contains your desired XML, then on the client side you could use a data URI to open the file using the XSL mime type, or send the file to the client using the Excel mimetype "Content-Type: application/vnd.ms-excel...
Force to open “Save As…” popup open at text link click for PDF in HTML
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If you give a string in the download attribute, it will be used as file name. I'm using it in userscripts all the time.
– weaknespase
Apr 9 '18 at 6:36
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Java int to String - Integer.toString(i) vs new Integer(i).toString()
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Integer.toString calls the static method in the class Integer. It does not need an instance of Integer.
If you call new Integer(i) you create an instance of type Integer, which is a full Java object encapsulating the value of your int...