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In Jinja2, how do you test if a variable is undefined?
... Additionally, you can use {% if variable is not defined %} to test the inverse.
– pbaranay
Feb 22 '17 at 15:37
...
How do you set a default value for a MySQL Datetime column?
...ith DATETIME...
But you can do it with TIMESTAMP:
mysql> create table test (str varchar(32), ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
Query OK, 0 rows affected (0.00 sec)
mysql> desc test;
+-------+-------------+------+-----+-------------------+-------+
| Field | Type | Null | Key | ...
How to rethrow InnerException without losing stack trace in C#?
...ctManager calls SetObjectData
// voila, e is unmodified save for _remoteStackTraceString
}
This wastes a lot of cycles compared to calling InternalPreserveStackTrace via cached delegate, but has the advantage of relying only on public functionality. Here are a couple of common usage patterns ...
Specifying colClasses in the read.csv
...nly one columns.
So in your example you should use:
data <- read.csv('test.csv', colClasses=c("time"="character"))
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How do you check if a variable is an array in JavaScript? [duplicate]
... the one you have chosen.
variable.constructor === Array
This is the fastest method on Chrome, and most likely all other browsers. All arrays are objects, so checking the constructor property is a fast process for JavaScript engines.
If you are having issues with finding out if an objects proper...
Disable ActiveRecord for Rails 4
...require "action_mailer/railtie"
require "sprockets/railtie"
require "rails/test_unit/railtie"
Remove config.active_record.raise_in_transactional_callbacks = true from config/application.rb
3. Delete your config/database.yml file, db/schema.rb and migrations (if any)
4. Delete migration check in ...
In Python, if I return inside a “with” block, will the file still close?
... experiment to show the guarantee you get from the finally keywrod is: def test(): try: return True; finally: return False.
– Ehsan Kia
Jul 11 '14 at 19:57
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What's a quick way to test to see a file exists?
...he directory's files, or I can try to open a specific file. What's the fastest way? I just need to know if the file is there or if it does not exist.
...
Java 8 NullPointerException in Collectors.toMap
...ault non-overloaded version instead. Maybe merge is faster, but I have not tested.
– Brett Ryan
Oct 19 '15 at 12:59
1
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How to reference generic classes and methods in xml documentation
...t completely resolves.
If the method in the OP were in a namespace called Test, the completely resolved link to the method shown would be:
<see cref="M:Test.FancyClass`1.FancyMethod``1(`0)"/>
As you may be able to work out, there should only be one backtick before the number of class type p...