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How to check if a variable is not null?
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This check is actually not safe. If myvar is 0, false or any other falsy value the test will fail (if you only intend to check for not null). So only use this to check for not null if the variable can never have another falsy value.
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Can Maven be made less verbose?
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In maven 3.5.x I actually need to enable --batch-mode (-B) for the -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=warn trick to work.
– Auke
Oct 20 '17 at 12:44
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Use of Java's Collections.singletonList()?
... a bit faster and/or save a bit of memory, but it is unlikely that these small savings will be significant. (An application that creates vast numbers of singleton lists is unusual to say the least.)
How does immutability play a role here?
It is part of the specification of the method; see ab...
How to make a window always stay on top in .Net?
...s app that runs a macro in another program. The other program will continually pop up windows and generally make things look, for lack of a better word, crazy. I want to implement a cancel button that will stop the process from running, but I cannot seem to get the window to stay on top. How do I...
node.js, Error: Cannot find module 'express'
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It says
Cannot find module 'express'
Do you have express installed?If not then run this.
npm install express
And run your program again.
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How to safely upgrade an Amazon EC2 instance from t1.micro to large? [closed]
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then delete small the instance before?
– gandil
May 5 '11 at 13:25
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What is the purpose of Order By 1 in SQL select statement?
...is only has the sql tag. In Standard SQL only column correlation names are allowed in the OREDER BY clause because, in theory, the table correlation names are out of scope i.e. should be ORDER BY PAYMENT_DATE;. Of course, not all SQL implementations conform to Standards.
– oned...
Error: Could not find or load main class [duplicate]
I am having trouble compiling and running my Java code, intended to allow me to interface Java with a shared object for Vensim, a simulation modeling package.
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Sql Server equivalent of a COUNTIF aggregate function
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I usually do what Josh recommended, but brainstormed and tested a slightly hokey alternative that I felt like sharing.
You can take advantage of the fact that COUNT(ColumnName) doesn't count NULLs, and use something like this:
S...
bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need
...nd followed this tutorial to get Beautiful Soup and lxml, which both installed successfully and work with a separate test file located here . In the Python script that causes this error, I have included this line:
from pageCrawler import comparePages
And in the pageCrawler file I have inclu...