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Safe (bounds-checked) array lookup in Swift, through optional bindings?
If I have an array in Swift, and try to access an index that is out of bounds, there is an unsurprising runtime error:
19 A...
Function in JavaScript that can be called only once
...y once, in each time after the first it won't be executed. I know from C++ and Java about static variables that can do the work but I would like to know if there is a more elegant way to do this?
...
Give examples of functions which demonstrate covariance and contravariance in the cases of both over
Please show a good example for covariance and contravariance in Java.
3 Answers
3
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HTML5 textarea placeholder not appearing
...not appear. It seems as though it may be covered up with some blank spaces and tabs. When you focus on the text area and delete from where the cursor puts itself, then leave the text area, the proper placeholder then appears.
...
How often should you use git-gc?
... on how much the repository is used. With one user checking in once a day and a branch/merge/etc operation once a week you probably don't need to run it more than once a year.
With several dozen developers working on several dozen projects each checking in 2-3 times a day, you might want to run it...
Using try vs if in python
...er LBYL style ("look before you leap"). To me, it's a matter of efficiency and readability.
In your example (say that instead of returning a list or an empty string, the function were to return a list or None), if you expect that 99 % of the time result will actually contain something iterable, I'd...
SQLAlchemy: What's the difference between flush() and commit()?
What the difference is between flush() and commit() in SQLAlchemy?
5 Answers
5
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How can I add an empty directory to a Git repository?
...esign of the git index
(staging area) only permits files to
be listed, and nobody competent enough
to make the change to allow empty
directories has cared enough about
this situation to remedy it.
Directories are added automatically
when adding files inside them. That
is, director...
Difference between and text
... you more layout freedom over the design of the button. In all its intents and purposes, it seemed excellent at first, but various browser quirks make it hard to use at times.
In your example, IE6 will send text to the server, while most other browsers will send nothing. To make it cross-browser c...
What is the difference between “pom” type dependency with scope “import” and without “import”?
...n then reference these dependencies in the dependency section of your POM (and all of its child POMs) without having to include a version etc.
However if in your POM you simply define a normal dependency to other-pom-artifact-id then all dependencies from the dependency section of the other-pom-art...