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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...owever not in the case of appending elements to the uninitialized array. isset() language construct can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not in...
What is your single most favorite command-line trick using Bash? [closed]
...ry, but did you know you can use <ctrl>-S to forward search if you set stty stop "" ? Also, have you ever tried running bind -p to see all of your keyboard shortcuts listed? There are over 455 on Mac OS X by default.
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How to get a list of current open windows/process with Java?
Does any one know how do I get the current open windows or process of a local machine using Java?
14 Answers
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Enum type constraints in C# [duplicate]
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This is an occasionally requested feature.
As I'm fond of pointing out, ALL features are unimplemented until someone designs, specs, implements, tests, documents and ships the feature. So far, no one has done that for this one. There's no particularly unusu...
How do I create a nice-looking DMG for Mac OS X using command-line tools?
...tore its name in the "backgroundPictureName" variable.
Use AppleScript to set the visual styles (name of .app must be in bash variable "applicationName", use variables for the other properties as needed):
echo '
tell application "Finder"
tell disk "'${title}'"
open
se...
How to know if two arrays have the same values
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If you don't care about the order of the members of the arrays, ES2015+'s Set may be a better data structure than Array. See the MDN notes on how to implement isSuperset and difference using dangerous monkey-patching.
share...
New line in Sql Query
... editor after snippets, if snippets enabled
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What is the difference between Int and Integer?
...e from -2147483647 to 2147483647,
while an Integer range from the whole Z set, that means, it can be arbitrarily large.
$ ghci
Prelude> (12345678901234567890 :: Integer, 12345678901234567890 :: Int)
(12345678901234567890,-350287150)
Notice the value of the Int literal.
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How to check iOS version?
... constant. This came up in iOS 8 with the introduction of UIApplicationOpenSettingsURLString, used to load Settings app via -openURL:. The value didn't exist prior to iOS 8. Passing nil to this API will crash, so you must take care to verify the existence of the constant first:
if (&UIApplicati...
Why do we always prefer using parameters in SQL statements?
...se don't use AddWithValue! It can cause implicit conversion issues. Always set the size explicitly and add the parameter value with parameter.Value = someValue.
– George Stocker
Mar 11 '15 at 15:41
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