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Why must a lambda expression be cast when supplied as a plain Delegate parameter

...her be converted to a delegate type or an expression tree - but it has to know which delegate type. Just knowing the signature isn't enough. For instance, suppose I have: public delegate void Action1(); public delegate void Action2(); ... Delegate x = () => Console.WriteLine("hi"); What woul...
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Illegal pattern character 'T' when parsing a date string to java.util.Date

... Update for Java 8 and higher You can now simply do Instant.parse("2015-04-28T14:23:38.521Z") and get the correct thing now, especially since you should be using Instant instead of the broken java.util.Date with the most recent versions of Java. You should be u...
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Integrating the ZXing library directly into my Android application

...ed folder and open the core directory and select core.jar ... hit enter! Now you just have to correct a few errors in the translations and the AndroidManifest.xml file :) Now you can happily compile, and you will now have a working standalone barcode scanner app, based on the ZXing source ;) Happ...
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In Python, how do you convert a `datetime` object to seconds?

... Python now warns me: "TypeError: can't subtract offset-naive and offset-aware datetimes" What's the best solution to fix that? – Aaron Ash Apr 13 '13 at 0:47 ...
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Checking if an Android application is running in the background

... activity state is briefly locked down to do the switch) that we actually know for sure what the next thing will be. And the implementation and global behavior here is not guaranteed to remain the same in the future. I wish I had read this before I posted an answer on the SO, but hopefully it...
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How do you serialize a model instance in Django?

... assuming obj is your model instance dict_obj = model_to_dict( obj ) You now just need one straight json.dumps call to serialize it to json: import json serialized = json.dumps(dict_obj) That's it! :) share | ...
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Is it possible to make abstract classes in Python?

...class is already established as abstract shouldn't the compiler/interpret know that all the methods are from the abstract class in question? – Charlie Parker Mar 17 '14 at 3:30 35 ...
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Is it a good idea to index datetime field in mysql?

...it in conditions frequently in queries. If your only condition is BETWEEN NOW() AND DATE_ADD(NOW(), INTERVAL 30 DAY) and you have no other index in the condition, MySQL will have to do a full table scan on every query. I'm not sure how many rows are generated in 30 days, but as long as it's less t...
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List goals/targets in GNU make that contain variables in their definition

...vial makefile, dummy.mk, with these contents: __all_targets__: ; #no-op Now invoke make as make -p -f Makefile -f dummy.mk __all_targets__. On any substantial build, the difference in the amount of output generated by make is significant. For example: $ gmake -pn | wc 138985 2632330 69612711 ...
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What is the list of possible values for navigator.platform as of today? [closed]

I know that this changes quite often, but is there a list as exhaustive as possible out there of the possible values returned by navigator.platform ? ...