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Java 8 NullPointerException in Collectors.toMap
The Java 8 Collectors.toMap throws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
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Select a Dictionary with LINQ
I have used the "select" keyword and extension method to return an IEnumerable<T> with LINQ, but I have a need to return a generic Dictionary<T1, T2> and can't figure it out. The example I learned this from used something in a form similar to the following:
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How to file split at a line number [closed]
... to do this on Windows and don't want to use Cygwin, this project provides all the needed utils as native win32 binaries - unxutils.sourceforge.net
– Jonathon Hill
Dec 30 '11 at 3:27
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How often does python flush to a file?
...t size.
A negative buffering means to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
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Combining two lists and removing duplicates, without removing duplicates in original list
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oops. You're right. Totally missed that the first list was allowed duplicates. :P
– staticd
Oct 3 '13 at 4:34
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Checkout another branch when there are uncommitted changes on the current branch
...st of the time when I try to checkout another existing branch, Git doesn't allow me if I have some uncommitted changes on the current branch. So I'll have to commit or stash those changes first.
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Why is isNaN(null) == false in JS?
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I believe the code is trying to ask, "is x numeric?" with the specific case here of x = null. The function isNaN() can be used to answer this question, but semantically it's referring specifically to the value NaN. From Wikipedia for NaN:
NaN (Not a Number) is...
How do I format a date in Jinja2?
...and print) the strftime() method in your template, for example
{{ car.date_of_manufacture.strftime('%Y-%m-%d') }}
Another, sightly better approach would be to define your own filter, e.g.:
from flask import Flask
import babel
app = Flask(__name__)
@app.template_filter()
def format_datetime(val...
Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine
...lution for this problem. The issue I described in my question occured basically due to the incompatibility of the Microsoft.Jet.OLEDB.4.0 driver in 64 bit OS.
So if we are using Microsoft.Jet.OLEDB.4.0 driver in a 64 bit server, we have to force our application to build in in 32 bit mode (This is ...
Java integer to byte array
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using Java NIO's ByteBuffer is very simple:
byte[] bytes = ByteBuffer.allocate(4).putInt(1695609641).array();
for (byte b : bytes) {
System.out.format("0x%x ", b);
}
output:
0x65 0x10 0xf3 0x29
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