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NULL vs nil in Objective-C
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227
nil should only be used in place of an id, what we Java and C++ programmers would think of as ...
Starting python debugger automatically on error
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edited Jun 1 '18 at 21:05
Ivan Castellanos
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How to know if an object has an attribute in Python
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2448
Try hasattr():
if hasattr(a, 'property'):
a.property
EDIT: See zweiterlinde's answer b...
Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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edited Aug 2 '17 at 10:42
a_horse_with_no_name
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Is there documentation for the Rails column types?
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2 Answers
2
Active
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Android View.getDrawingCache returns null, only null
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240
I was having this problem also and found this answer:
v.setDrawingCacheEnabled(true);
// thi...
How to initialize a struct in accordance with C programming language standards
...ializer to initialize a structure:
MY_TYPE a = { .flag = true, .value = 123, .stuff = 0.456 };
Edit: Other members are initialized as zero: "Omitted field members are implicitly initialized the same as objects that have static storage duration." (https://gcc.gnu.org/onlinedocs/gcc/Designated-Ini...
What is digest authentication?
...03 Forbidden (access denied).
Digest authentication is standardized in RFC2617. There's a nice overview of it on Wikipedia:
You can think of it like this:
Client makes request
Client gets back a nonce from the server and a 401 authentication request
Client sends back the following response arra...
Git Commit Messages: 50/72 Formatting
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284
Regarding the “summary” line (the 50 in your formula), the Linux kernel documentation has...
Implementing MVC with Windows Forms
...e seen are (including most combinations):
Directly talk to the database (2 tier)
Use a backend that has been written for the given application (3 tier)
Use a set of web services that were written for use by many applications and can’t be changed for your application. (Service-oriented architectu...