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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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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...
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...
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...
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...
Using Transactions or SaveChanges(false) and AcceptAllChanges()?
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452
With the Entity Framework most of the time SaveChanges() is sufficient. This creates a transacti...
sql primary key and index
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answered Jan 20 '09 at 18:51
dkretzdkretz
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How do I find out what version of WordPress is running?
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254
Look in wp-includes/version.php
/**
* The WordPress version string
*
* @global string $wp_...