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PHP Regex to check date is in YYYY-MM-DD format

... Try this. $date="2012-09-12"; if (preg_match("/^[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[1-2][0-9]|3[0-1])$/",$date)) { return true; } else { return false; } share | ...
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Check if a string contains another string

I want to find if a string contains a ","(comma) in it. Do we have any other option other than reading char-by-char? 4 Answ...
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How can I multiply all items in a list together with Python?

...ordsforthewise without the third argument, it throws a TypeError exception if you pass it an empty sequence – Francisco Couzo Jul 11 '16 at 3:41 1 ...
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How to calculate time in hours between two dates in iOS

...culate the time elapsed in hours between two times (possibly occurring on different days) in iOS? 5 Answers ...
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Default argument values in JavaScript functions [duplicate]

... In javascript you can call a function (even if it has parameters) without parameters. So you can add default values like this: function func(a, b){ if (typeof(a)==='undefined') a = 10; if (typeof(b)==='undefined') b = 20; //your code } and then you can ca...
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Check if key exists and iterate the JSON array using Python

...id_7"}""" def getTargetIds(jsonData): data = json.loads(jsonData) if 'to' not in data: raise ValueError("No target in given data") if 'data' not in data['to']: raise ValueError("No data for target") for dest in data['to']['data']: if 'id' not in dest: ...
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How to tell Jackson to ignore a field during serialization if its value is null?

How can Jackson be configured to ignore a field value during serialization if that field's value is null. 19 Answers ...
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Random record from MongoDB

...m the mycoll collection. db.mycoll.aggregate([{ $sample: { size: 1 } }]) If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline: // Get one random document matching {a: 10} from the mycoll collection. db.mycoll.aggregate([ ...
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Return type of '?:' (ternary conditional operator)

...alue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues and prvalues.) In very broad and simple terms, an lvalue refers to an object in memory and an rvalue is just a value that may not necessarily be attached to an object in memory. An...
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How to tell if a file is git tracked (by shell exit code)?

Is there a way to tell if a file is being tracked by running some git command and checking its exit code? 8 Answers ...