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Aren't Python strings immutable? Then why does a + “ ” + b work?

...u changed the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want. share | improve ...
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How do I tell if a regular file does not exist in Bash?

...tmp/foo.txt ] && echo "File not found!" – DavidWinterbottom Sep 29 '10 at 12:09 38 ...
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How can I change an element's class with JavaScript?

...iques for changing classes Modern browsers have added classList which provides methods to make it easier to manipulate classes without needing a library: document.getElementById("MyElement").classList.add('MyClass'); document.getElementById("MyElement").classList.remove('MyClass'); if ( document...
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How to make an Android Spinner with initial text “Select One”?

... Here's a general solution that overrides the Spinner view. It overrides setAdapter() to set the initial position to -1, and proxies the supplied SpinnerAdapter to display the prompt string for position less than 0. This has been tested on Android 1.5 through 4...
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ASP.NET MVC 5 - Identity. How to get current ApplicationUser

...PI is consistent. For example the users table is now called AspNetUsers in Identity Framework, and the names of several primary key fields kept changing, so the code in several answers will no longer work as-is. Another problem is that the underlying OWIN access to the database will use a separate ...
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Data Modeling with Kafka? Topics and Partitions

...o in the example above, I would just have a single topic and if you´ll decide to push some other kind of data through Kafka, you can add a new topic for that later. Topics are registered in ZooKeeper which means that you might run into issues if trying to add too many of them, e.g. the case where ...
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How to check if a column exists in a SQL Server table?

...ROM sys.columns WHERE Name = N'columnName' AND Object_ID = Object_ID(N'schemaName.tableName')) BEGIN -- Column Exists END Martin Smith's version is shorter: IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL BEGIN -- Column Exists END ...
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Entity framework self referencing loop detected [duplicate]

...u want example (psuedo)code: departments.select(dep => new { dep.Id, Employee = new { dep.Employee.Id, dep.Employee.Name } }); share | improve this answer | ...
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How to set RelativeLayout layout params in code not in xml?

...utParams.WRAP_CONTENT); params.addRule(RelativeLayout.RIGHT_OF, button1.getId()); Button button2; button2.setLayoutParams(params); As you can see, this is what you have to do: Create a RelativeLayout.LayoutParams object. Use addRule(int) or addRule(int, int) to set the rules. The first method is...
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Bootstrap: Open Another Modal in Modal

... ordered in your Html markup from lowest to highest. $(document).on('hidden.bs.modal', function (event) { if ($('.modal:visible').length) { $('body').addClass('modal-open'); } }); UPDATE: When you have stacked modals, all the backdrops appear below the lowermost modal. You c...