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What's the idiomatic syntax for prepending to a short python list?
...icient, because in Python, a list is an array of pointers, and Python must now take every pointer in the list and move it down by one to insert the pointer to your object in the first slot, so this is really only efficient for rather short lists, as you ask.
Here's a snippet from the CPython source...
What does send() do in Ruby?
...s, so that you can call private methods, too (useful for unit testing).
If there is really no variable before send, that means that the global Object is used:
send :to_s # "main"
send :class # Object
share
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Converting NSString to NSDate (and back again)
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Swift 4 and later
Updated: 2018
String to Date
var dateString = "02-03-2017"
var dateFormatter = DateFormatter()
// This is important - we set our input date format to match our input string
// if the format doesn't match y...
Convert JSON to Map
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I like google gson library.
When you don't know structure of json. You can use
JsonElement root = new JsonParser().parse(jsonString);
and then you can work with json. e.g. how to get "value1" from your gson:
String value1 = root.getAsJsonObject().get("data").getAsJ...
Setting a property by reflection with a string value
...ersions are possible, though, and you may need to write special case logic if you want to support conversions from types that are not IConvertible.
The corresponding code (without exception handling or special case logic) would be:
Ship ship = new Ship();
string value = "5.5";
PropertyInfo propert...
How do you convert a time.struct_time object into a datetime object?
...9, tm_hour=23, tm_min=57, tm_sec=42, tm_wday=0, tm_yday=252, tm_isdst=0)
Now note what you actually get with the "published" field.
Mon, 09 Sep 2013 19:57:42 -0400
By Stallman's Beard! Timezone information!
In this case, the lazy man might want to use the excellent dateutil module to keep the ...
Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY nam...
How to change a table name using an SQL query?
...', 'Stu_Table_10'
You can find documentation on this procedure on MSDN.
If you need to include a schema name, this can only be included in the first parameter (that is, this cannot be used to move a table from one schema to another). So, for example, this is valid:
EXEC sp_rename 'myschema.Stu_T...
Grep characters before and after match?
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What's the significance of the first number in the curly-bracketed pairs? Like the 0s in "grep -E -o ".{0,5}test_pattern.{0,5}" test.txt "?
– Lew Rockwell Fan
Jun 23 '17 at 2:28
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Histogram Matplotlib
... I have the center of the bins and the number of events per bin. How can I now plot is as a histogram. I tried just doing
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