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Why Choose Struct Over Class?

...you want to choose a Struct instead of a Class? Seems like they are the same thing, with a Struct offering less functionality. Why choose it then? ...
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Bootstrap 3 Navbar with Logo

...f doing this without causing any issues with different screen sizes? I assume this a common requirement, but I haven't yet seen a good code sample. A key requirement other than having acceptable display on all screen sizes is the menu collapsibility on smaller screens. ...
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How to trace the path in a Breadth-First Search?

...n.wikipedia.org/wiki/Breadth-first_search first. Below is a quick implementation, in which I used a list of list to represent the queue of paths. # graph is in adjacent list representation graph = { '1': ['2', '3', '4'], '2': ['5', '6'], '5': ['9', '10'], '4': ['...
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Create unique constraint with null columns

...ial indexes: CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id) WHERE menu_id IS NOT NULL; CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id) WHERE menu_id IS NULL; This way, there can only be one combination of (user_id, recipe_id) where menu_i...
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When should I use mmap for file access?

POSIX environments provide at least two ways of accessing files. There's the standard system calls open() , read() , write() , and friends, but there's also the option of using mmap() to map the file into virtual memory. ...
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How to create an object for a Django model with a many to many field?

...erates a whopping total of 7 queries: SELECT "app_bar"."id", "app_bar"."name" FROM "app_bar" WHERE "app_bar"."id" = 1 SELECT "app_bar"."id", "app_bar"."name" FROM "app_bar" WHERE "app_bar"."id" = 2 INSERT INTO "app_foo" ("name") VALUES () SELECT "app_foo_bars"."bar_id" FROM "app_foo_bars" WHERE ("a...
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What is the difference between a string and a byte string?

...se in order to do the conversion, since a different encoding may map the same bytes to a different string: >>> b'\xcf\x84o\xcf\x81\xce\xbdo\xcf\x82'.decode('utf-16') '蓏콯캁澽苏' >>> b'\xcf\x84o\xcf\x81\xce\xbdo\xcf\x82'.decode('utf-8') 'τoρνoς' Once you know which one...
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How to correctly close a feature branch in Mercurial?

I've finished working on a feature branch feature-x . I want to merge results back to the default branch and close feature-x in order to get rid of it in the output of hg branches . ...
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Chaining multiple filter() in Django, is this a bug?

I always assumed that chaining multiple filter() calls in Django was always the same as collecting them in a single call. 4...
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Are global variables bad? [closed]

... global variables is that since every function has access to these, it becomes increasingly hard to figure out which functions actually read and write these variables. To understand how the application works, you pretty much have to take into account every function which modifies the global state....