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How do I compare version numbers in Python?

...on) True >>> version.Version("1.3.xy123") Traceback (most recent call last): ... packaging.version.InvalidVersion: Invalid version: '1.3.xy123' packaging.version.parse is a third-party utility but is used by setuptools (so you probably already have it installed) and is conformant to the c...
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Stack, Static, and Heap in C++

...t understood very well these three concepts. When do I have to use dynamic allocation (in the heap) and what's its real advantage? What are the problems of static and stack? Could I write an entire application without allocating variables in the heap? ...
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Why can't we have static method in a (non-static) inner class?

... would be 'annoying as a mothertrucker'. Don't understand why Java doesn't allow for this. Sometimes, I want an inner class to use properties of the parent class, but keep static methods for better namespacing. Is there something inherently wrong with this? :( – Angad ...
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Rails: What's a good way to validate links (URLs)?

...l probably reject the following host http://invalid##host.com but it will allow http://invalid-host.foo that is a valid host, but not a valid domain if you consider the existing TLDs. Indeed, the solution would work if you want to validate the hostname, not the domain because the following one is ...
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Escape string for use in Javascript regex [duplicate]

...mp;'); // $& means the whole matched string } Example escapeRegExp("All of these should be escaped: \ ^ $ * + ? . ( ) | { } [ ]"); >>> "All of these should be escaped: \\ \^ \$ \* \+ \? \. \( \) \| \{ \} \[ \] " (NOTE: the above is not the original answer; it was edited to show th...
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What are my environment variables? [closed]

... I am not sure if thats what you want, but try printenv This will show you all your environment variables. About where they are stored Linux: where are environment variables stored? How to set Shell Environment Variables http://www.codecoffee.com/tipsforlinux/articles/030.html Happy reading :-)...
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Python initializing a list of lists [duplicate]

... The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the sam...
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Replacing all non-alphanumeric characters with empty strings

... Use [^A-Za-z0-9]. Note: removed the space since that is not typically considered alphanumeric. share | improve this answer | follow | ...
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Laravel: Get base url

...\UrlGenerator; class Classname { protected $url; public function __construct(UrlGenerator $url) { $this->url = $url; } public function methodName() { $this->url->to('/'); } } ...
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How to get all selected values from ?

...ipt as many people do not use JQuery in their sites. From RobG How to get all selected values of a multiple select box using JavaScript?: function getSelectValues(select) { var result = []; var options = select && select.options; var opt; for (var i=0, iLen=options.length; i<...