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Pointers in Python?
...rm.field.value to always have the
same value
This is feasible, because it involves decorated names and indexing -- i.e., completely different constructs from the barenames a and b that you're asking about, and for with your request is utterly impossible. Why ask for something impossible and tot...
“loop:” in Java code. What is this, and why does it compile?
...
It is not a keyword it is a label.
Usage:
label1:
for (; ; ) {
label2:
for (; ; ) {
if (condition1) {
// break outer loop
break label1;
}
...
What does 'super' do in Python?
...
The benefits of super() in single-inheritance are minimal -- mostly, you don't have to hard-code the name of the base class into every method that uses its parent methods.
However, it's almost impossible to use multiple-inheritance w...
shortcut for creating a Map from a List in groovy?
...ovy version 1.7.9 came out, so the method collectEntries didn't exist yet. It works exactly as the collectMap method that was proposed:
Map rowToMap(row) {
row.columns.collectEntries{[it.name, it.val]}
}
If for some reason you are stuck with an older Groovy version, the inject method can also...
Visual Studio : short cut Key : Duplicate Line
...io 2017 (v15.6 and after)
Ctrl + D
In Visual Studio 2017 (pre v15.6)
(edit) This feature is now built-in in VS2017: Ctrl + E, V duplicates a line if nothing is selected, or duplicates selection. You can assign it to a different key combination, or find it in the menu:
See this reference for mo...
Why does C# disallow readonly local variables?
Having a friendly debate with a co-worker about this. We have some thoughts about this, but wondering what the SO crowd thinks about this?
...
What's the scope of the “using” declaration in C++?
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When you #include a header file in C++, it places the whole contents of the header file into the spot that you included it in the source file. So including a file that has a using declaration has the exact same effect of placing the using declaration at the top of ...
What is a JavaBean exactly?
I understood, I think, that a "Bean" is a Java class with properties and getters/setters. As much as I understand, it is the equivalent of a C struct. Is that true?
...
What's the _ underscore representative of in Swift References?
...
Both answers were correct but I want to clarify a little bit more.
_ is used to modify external parameter name behavior for methods.
In Local and External Parameter Names for Methods section of the documentation, it says:
Swift gives the first parameter name in a method...
Database development mistakes made by application developers [closed]
...
1. Not using appropriate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the queries you nee...