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list.clear() vs list = new ArrayList(); [duplicate]
... @RMT : Answer sounds unarguable.
– theapache64
May 20 '16 at 10:32
Sure, if the list is big or not, a clear h...
PostgreSQL create table if not exists
... until i saw this one. This does help a bit.
– Angry 84
Mar 16 '18 at 9:32
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How to do Mercurial's 'hg remove' for all missing files?
...ed-file-2" removed-file-1 removed-file-2
committed changeset 185:628800a7af84
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.keyCode vs. .which
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David TangDavid Tang
84.3k2828 gold badges156156 silver badges144144 bronze badges
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Rollback to an old Git commit in a public repo
...This is previous commit message
commit ab0de062136da650ffc27cfb57febac8efb84b8d
Author: author <author@gmail.com>
Date: Thu Jun 23 00:41:55 2016 +0300
This is previous previous commit message
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Step 2: copy needed commit hash and paste it for checkout:
git checkout fd6cb176297acca4dbc...
Objective-C : BOOL vs bool
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From the definition in objc.h:
#if (TARGET_OS_IPHONE && __LP64__) || TARGET_OS_WATCH
typedef bool BOOL;
#else
typedef signed char BOOL;
// BOOL is explicitly signed so @encode(BOOL) == "c" rather than "C"
// even if -funsigned-char is used.
#endif
#define YES ((BOOL)1)
#define NO...
How fast is D compared to C++?
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64
To enable all optimizations and disable all safety checks, compile your D program with the foll...
How does '20 seconds' work in Scala?
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84
Any sufficiently advanced technology is indistinguishable from magic.
– ripper234
Feb 27 '13 at 5:32...
Add column with number of days between dates in DataFrame pandas
...f['B'] = pd.to_datetime(df['B'])
In [11]: df.dtypes # if already datetime64 you don't need to use to_datetime
Out[11]:
A datetime64[ns]
B datetime64[ns]
dtype: object
In [12]: df['A'] - df['B']
Out[12]:
one -58 days
two -26 days
dtype: timedelta64[ns]
In [13]: df['C'] = df['A'] - df['B...
Store JSON object in data attribute in HTML jQuery
...se, i just found the answer to that question here: stackoverflow.com/a/42864472 "You don't need to stringify objects to store them using jQuery.data()"
– user1063287
Aug 7 '19 at 8:04
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