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1500 questions
1350
votes
28 answers

What is the difference between null=True and blank=True in Django?

When we add a model field in Django we generally write: models.CharField(max_length=100, null=True, blank=True) The same is done with ForeignKey, DecimalField etc. What is the basic difference between: null=True only blank=True only null=True and…
user993563
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1348
votes
15 answers

How do I check if a variable exists?

I want to check if a variable exists. Now I'm doing something like this: try: myVar except NameError: # Do something. Are there other ways without exceptions?
Max Frai
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1348
votes
17 answers

Correct way to write line to file?

How do I write a line to a file in modern Python? I heard that this is deprecated: print >>f, "hi there" Also, does "\n" work on all platforms, or should I use "\r\n" on Windows?
Yaroslav Bulatov
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1347
votes
35 answers

Access-Control-Allow-Origin Multiple Origin Domains?

Is there a way to allow multiple cross-domains using the Access-Control-Allow-Origin header? I'm aware of the *, but it is too open. I really want to allow just a couple domains. As an example, something like this: Access-Control-Allow-Origin:…
Thomas J Bradley
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1345
votes
22 answers

Why do people write "#!/usr/bin/env python" on the first line of a Python script?

I see these at the top of Python files: #!/usr/bin/env python #!/usr/bin/env python3 It seems to me that the files run the same without that line.
john garcias
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1345
votes
14 answers

SOAP vs REST (differences)

I have read articles about the differences between SOAP and REST as a web service communication protocol, but I think that the biggest advantages for REST over SOAP are: REST is more dynamic, no need to create and update UDDI(Universal…
Abdulaziz
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1344
votes
18 answers

How do I set/unset a cookie with jQuery?

How do I set and unset a cookie using jQuery, for example create a cookie named test and set the value to 1?
omg
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1343
votes
13 answers

How to reload a page using JavaScript

How can I reload the page using JavaScript? I need a method that works in all browsers.
Resh
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1343
votes
13 answers

git: undo all working dir changes including new files

How to delete all changes from working directory including new untracked files. I know that git checkout -f does that, but it doesn't delete new untracked files created since last commit. Does anybody have an idea how to do that?
Aler
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1342
votes
42 answers

What's the difference between a mock & stub?

I've read various articles about mocking vs stubbing in testing, including Martin Fowler's Mocks Aren't Stubs, but still don't understand the difference.
never_had_a_name
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1342
votes
13 answers

UTF-8 all the way through

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1. Where exactly do I need to set the encoding/charsets?…
mercutio
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1342
votes
26 answers

How should I ethically approach user password storage for later plaintext retrieval?

As I continue to build more and more websites and web applications I am often asked to store user's passwords in a way that they can be retrieved if/when the user has an issue (either to email a forgotten password link, walk them through over the…
Shane
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1342
votes
33 answers

Difference between "wait()" vs "sleep()" in Java

What is the difference between a wait() and sleep() in Threads? Is my understanding that a wait()-ing Thread is still in running mode and uses CPU cycles but a sleep()-ing does not consume any CPU cycles correct? Why do we have both wait() and…
Geek
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1340
votes
17 answers

Replace one substring for another string in shell script

I have "I love Suzi and Marry" and I want to change "Suzi" to "Sara". firstString="I love Suzi and Marry" secondString="Sara" Desired result: firstString="I love Sara and Marry"
Zincode
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1339
votes
27 answers

How do I collapse sections of code in Visual Studio Code for Windows?

How do I fold or collapse sections of code in Visual Studio Code? Is this feature supported?
Nick
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