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How to check if a map contains a key in Go?

...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map evaluates ok, which will be true if "foo" was in the map If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope. ...
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Laravel migration: unique key is too long, even if specified

... Specify a smaller length for your e-mail: $table->string('email', 250); Which is the default, actually: $table->string('email'); And you should be good. For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified ...
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What is the LD_PRELOAD trick?

...ibrary (including the C runtime, libc.so). So to run ls with your special malloc() implementation, do this: $ LD_PRELOAD=/path/to/my/malloc.so /bin/ls share | improve this answer | ...
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In Python, when should I use a function instead of a method?

...sulation which is so dear to OO design. The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
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Python constructor and default value [duplicate]

...class below, the wordList and adjacencyList variable is shared between all instances of Node. 4 Answers ...
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Delete all documents from index/type without deleting type

I know one can delete all documents from a certain type via deleteByQuery. 15 Answers ...
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Convert JavaScript string in dot notation into an object reference

...k themselves the question "why am I doing this?" It is of course generally fine to do this if your use case is small and you will not run into performance issues, AND you won't need to build upon your abstraction to make it more complicated later. In fact, if this will reduce code complexity an...
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How to use a custom comparison function in Python 3?

...e a workaround, but I think I am going to lose some performance by passing all the comparison operators < > = to middle man, since my original custom sort is written in C , it had around 1/2x speed of default sort. – YOU Mar 28 '10 at 5:26 ...
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What do the python file extensions, .pyc .pyd .pyo stand for?

... .py: This is normally the input source code that you've written. .pyc: This is the compiled bytecode. If you import a module, python will build a *.pyc file that contains the bytecode to make importing it again later easier (and faster). .pyo...
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?

...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...