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How to check if a file exists in Documents folder?
...nd handle those errors gracefully than it is to try to figure out ahead of time whether the operation will succeed. For more information on file system race conditions, see “Race Conditions and Secure File Operations” in Secure Coding Guide.
Source: Apple Developer API Reference
From the secure...
When to use a linked list over an array/array list?
...
Linked lists are preferable over arrays when:
you need constant-time insertions/deletions from the list (such as in real-time computing where time predictability is absolutely critical)
you don't know how many items will be in the list. With arrays, you may need to re-declare and copy me...
Using the Underscore module with Node.js
... to get the Underscore library to work properly... it seems that the first time I use a function from Underscore, it overwrites the _ object with the result of my function call. Anyone know what's going on? For example, here is a session from the node.js REPL:
...
Why do Lua arrays(tables) start at 1 instead of 0?
... a historical, marketing reason. No rational reason, especially at current time. And it seems even you're trying to avoid 1-based indexing instead of utilizing it :)
– eonil
Aug 7 '10 at 15:26
...
Service vs IntentService in the Android platform
... the application's main loop), but only one request will be processed at a time.
The IntentService class provides a straightforward structure for running an operation on a single background thread. This allows it to handle long-running operations without affecting your user interface's responsivene...
What is a “feature flag”?
...ing is on production infrastructure with production traffic. Don’t waste time building extensive performance labs and staging environments.
Experimentation - know how a new feature moves the needle on your KPIs.
Avoiding Hotfixes or Code Rollbacks when Problems Happen - both hotfixes and code ro...
Uses for Optional
...you're storing into a field, you'd do this at initialization or assignment time. If you're adding values into a list, as the OP mentioned, you have the additional choice of simply not adding the value, thereby "flattening" out absent values.
I'm sure somebody could come up with some contrived cases...
Why does the order of the loops affect performance when iterating over a 2D array?
...ed the i and j variables around. They both run in different amounts of time. Could someone explain why this happens?
7 ...
How can I dynamically create derived classes from a base class
... good practice in Python - you either have
variable names, known at coding time, or data - and names learned in runtime
are more "data" than "variables" -
So, you could just add your classes to a dictionary and use them from there:
name = "SpecialClass"
classes = {}
classes[name] = ClassFactory(n...
How to avoid null checking in Java?
... return empty collections (or arrays) instead of nulls pretty much all the time.
With non-collections it might be harder. Consider this as an example: if you have these interfaces:
public interface Action {
void doSomething();
}
public interface Parser {
Action findAction(String userInput);
...