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Swift: Testing optionals for nil
... : NSString?
if xyz {
// Do something using `xyz`.
}
This produces an error:
does not conform to protocol 'BooleanType.Protocol'
You have to use one of these forms:
if xyz != nil {
// Do something using `xyz`.
}
if let xy = xyz {
// Do something using `xy`.
}
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What integer hash function are good that accepts an integer hash key?
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Multiprocessing: How to use Pool.map on a function defined in a class?
...map on some functions that passed around a defaultdict and got the PicklingError again. I did not figure out a solution to this, I just reworked my code to not use the defaultdict.
– sans
Jul 8 '11 at 23:41
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How to send a simple string between two programs using pipes?
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printf("Received: %s\n", buf);
close(fd);
return 0;
}
Note: Error checking was omitted from the above code for simplicity.
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Include .so library in apk in android studio [duplicate]
...r with android app . I have followed the steps and it compiles without any error. But, at runtime it throws UnsatisfiedLinkError .
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How do I change the highlight style in Vim spellcheck?
Right now, when I do :set spell in my Vim, I get spelling errors highlighted as if they are selected text. What I want is an MS-Word like underlining of spelling errors. I tried to lookup :help spell but could not find a clue. Any help is appreciated.
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Team city unmet requirement: MSBuildTools12.0_x86_Path exists
...etting "MSBuild ToolsVersion" was set to 12.0 (default), which lead to the error "Unmet requirements: MSBuildTools12.0_x86_Path exists" on my system. Because I don't need the new MSBuild 12.0 to run my build, I changed this setting to 4.0 in my build step. This MSBuild version is correctly installed...
What do the f and t commands do in Vim?
Can somebody explain to me what the f and t commands do in vim and exactly how they work? I can't seem to find this information but people keep telling me that they are very useful. Would really appreciate an answer with an example if possible, thanks!
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List vs List
...myMap;
withWilds( myMap ); // Works
noWilds( myMap ); // Compiler error
}
You would think a List of HashMaps should be a List of Maps, but there's a good reason why it isn't:
Suppose you could do:
List<HashMap<String,String>> hashMaps = new ArrayList<HashMap<String,Str...
How to configure Ruby on Rails with no database?
...rage.service = :local # For Rails >= 5.2
config.active_record.migration_error = :page_load
config.active_record.verbose_query_logs = true
# config/environments/test.rb
config.active_storage.service = :test # For Rails >= 5.2
# config/environments/production.rb
config.active_storage.service =...