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Python: try statement in a single line
...variables to something. If they might not get set, set them to None first (or 0 or '' or something if it is more applicable.)
If you do assign all the names you are interested in first, you do have options.
The best option is an if statement.
c = None
b = [1, 2]
if c is None:
a = b
else:...
JavaScript by reference vs. by value [duplicate]
I'm looking for some good comprehensive reading material on when JavaScript passes something by value and when by reference and when modifying a passed item affects the value outside a function and when not. I'm also interested in when assigning to another variable is by reference vs. by value and ...
Create the perfect JPA entity [closed]
I've been working with JPA (implementation Hibernate) for some time now and each time I need to create entities I find myself struggling with issues as AccessType, immutable properties, equals/hashCode, ... .
So I decided to try and find out the general best practice for each issue and write this ...
Combine two ActiveRecord::Relation objects
...rst_name_relation.merge(last_name_relation)
If you want to combine using OR (union), use or†:
first_name_relation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install the where-or backport.
share
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Pointers vs. values in parameters and return values
In Go there are various ways to return a struct value or slice thereof. For individual ones I've seen:
4 Answers
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What is an anti-pattern?
...n patterns which are common approaches to common problems which have been formalized and are generally considered a good development practice, anti-patterns are the opposite and are undesirable.
For example, in object-oriented programming, the idea is to separate the software into small pieces call...
Does Java SE 8 have Pairs or Tuples?
...
UPDATE: This answer is in response to the original question, Does Java SE 8 have Pairs or Tuples? (And implicitly, if not, why not?) The OP has updated the question with a more complete example, but it seems like it can be solved without using any kind of Pair struct...
Android destroying activities, killing processes
Hi I'm wondering how Android is managing memory and I can't find precise answer anywhere.
Let's assume I have an application with 5 activities on current activity stack (4 are stopped and 1 is resumed), there is no service connected. I press HOME button so that all of my activities are stopped.
I st...
abort, terminate or exit?
...om there. This means that you are guaranteed that stack unwinding happens correctly and all destructors are called. In other words:
int main() {
try {
// your stuff
}
catch( ... ) {
return 1; // or whatever
}
}
...
Determine whether JSON is a JSONObject or JSONArray
I am going to receive either a JSON Object or Array from server, but I have no idea which it will be. I need to work with the JSON, but to do so, I need to know if it is an Object or an Array.
...