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Is it possible only to declare a variable without assigning any value in Python?
...ython is dynamic, so you don't need to declare things; they exist automatically in the first scope where they're assigned. So, all you need is a regular old assignment statement as above.
This is nice, because you'll never end up with an uninitialized variable. But be careful -- this doesn't mean...
spring boot default H2 jdbc connection (and H2 console)
...ething to enter when starting the H2 console (in this case, "AZ"). I think all of these are required though it seems like leaving out the spring.jpa.database-platform does not hurt anything.
In application.properties:
spring.datasource.url=jdbc:h2:mem:AZ;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE
s...
Javascript objects: get parent [duplicate]
...}.init();
Inside the init function you can get the parent object simply calling this.
So we define the parent property directly inside the child object.
Then (optionally) we can remove the init method.
Finally we give the main object back as output from the init function.
If you try to get main...
How to go to each directory and execute a command?
...oesn't match anything else than numbers, but in the general case, you basically always want to put the directory name in double quotes inside the loop. cd "$d" would be better in that it transfers to situations where the wildcard does match files whose names contain whitespace and/or shell metachar...
How do you beta test an iphone app?
...
In year 2011, there's a new service out called "Test Flight", and it addresses this issue directly.
Apple has since bought TestFlight in 2014 and has integrated it into iTunes Connect and App Store Connect.
...
RegEx to parse or validate Base64 data
...
The simplest solution would be to strip out all whitespace (which is ignored as per the RFC) before validation.
– Ben Blank
Jan 24 '09 at 1:35
2
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How to zip a whole folder using PHP
...$name => $file)
{
// Skip directories (they would be added automatically)
if (!$file->isDir())
{
// Get real and relative path for current file
$filePath = $file->getRealPath();
$relativePath = substr($filePath, strlen($rootPath) + 1);
// Add cur...
Cannot make a static reference to the non-static method
...
Since getText() is non-static you cannot call it from a static method.
To understand why, you have to understand the difference between the two.
Instance (non-static) methods work on objects that are of a particular type (the class). These are created with the new ...
The Concept of 'Hold space' and 'Pattern space' in sed
... line. So what happens is this:
first line is read and inserted automatically into the pattern space
on the first line, first command is not executed; h copies the first line into the hold space.
now the second line replaces whatever was in the pattern space
on the second line, first we execute G,...
How does the Comma Operator work
...t", "xor";
Notice that due to operator precedence, the code is (intentionally!) identical to
(((keywords = "and"), "or"), "not"), "xor";
That is, the first operator called is keywords.operator =("and") which returns a proxy object on which the remaining operator,s are invoked:
keywords.operato...
