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What's the point of map in Haskell, when there is fmap?
...ctually how it happens. What happened was that the type of map was generalized to cover Functor in Haskell 1.3. I.e., in Haskell 1.3 fmap was called map. This change was then reverted in Haskell 1.4 and fmap was introduced. The reason for this change was pedagogical; when teaching Haskell to beginne...
Repeater, ListView, DataList, DataGrid, GridView … Which to choose?
...bDude
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ReadOnlyCollection or IEnumerable for exposing member collections?
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Implementing MVC with Windows Forms
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Using Transactions or SaveChanges(false) and AcceptAllChanges()?
...tkins
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answered May 2 '09 at 21:24
Alex JamesAlex James
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What Content-Type value should I send for my XML sitemap?
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answered Jul 17 '10 at 17:40
GumboGumbo
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CSS display:table-row does not expand when width is set to 100%
...P.KP.
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node.js child process - difference between spawn & fork
... ratio, or for node processes heavy on I/O and light on CPU work, to minimize the down time the event loop is waiting for new events. However, the latter suggestion is a micro-optimization, and would need careful benchmarking to ensure your situation suits the need for many processes/core. You can...
PostgreSQL return result set as JSON array?
...Nulls
Aggregate functions typically give back NULL when they operate over zero rows. If this is a possibility, you might want to use COALESCE to avoid them. A couple of examples:
SELECT COALESCE(json_agg(t), '[]'::json) FROM t
Or
SELECT to_jsonb(COALESCE(array_agg(t), ARRAY[]::t[])) FROM t
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How is set() implemented?
...h dummy values (the keys being the members of the set), with some
optimization(s) that exploit this lack of values
So basically a set uses a hashtable as its underlying data structure. This explains the O(1) membership checking, since looking up an item in a hashtable is an O(1) operation, on a...