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if/else in a list comprehension
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You can totally do that. It's just an ordering issue:
[unicode(x.strip()) if x is not None else '' for x in row]
In general,
[f(x) if condition else g(x) for x in sequence]
And, for list comprehensions with if conditions only,
[f...
Count the items from a IEnumerable without iterating?
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I usually just grab List and IList out of habit. But especially if you want to implement them yourself ICollection is easier and also has the Count property. Thanks!
– Mendelt
Oct 3 '08 at 22...
Check whether a string matches a regex in JS
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Use regex.test() if all you want is a boolean result:
console.log(/^([a-z0-9]{5,})$/.test('abc1')); // false
console.log(/^([a-z0-9]{5,})$/.test('abc12')); // true
console.log(/^([a-z0-9]{5,})$/.test('abc123')); // true
...and ...
In ASP.NET, when should I use Session.Clear() rather than Session.Abandon()?
...n and the Session_OnEnd event is triggered.
Session.Clear() just removes all values (content) from the Object. The session with the same key is still alive.
So, if you use Session.Abandon(), you lose that specific session and the user will get a new session key. You could use it for example when ...
Conditional formatting based on another cell's value
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Note: when it says "B5" in the explanation below, it actually means "B{current_row}", so for C5 it's B5, for C6 it's B6 and so on. Unless you specify $B$5 - then you refer to one specific cell.
This is supported in Google Sheets as of 2015:
https://support.google.com/drive/answe...
How to inspect FormData?
...oo, bar)To take any number of argument you could use the apply method and call it as such: console.log.apply(console, array).
But there is a new ES6 way to apply arguments with spread operator and iteratorconsole.log(...array).
Knowing this, And the fact that FormData and both array's has a Symbol....
Git Cherry-pick vs Merge Workflow
...f a commit identifies it not just in and of itself but also in relation to all other commits that precede it. This offers you a guarantee that the state of the repository at a given SHA1 is identical across all clones. There is (in theory) no chance that someone has done what looks like the same c...
handle textview link click in my android app
...I simply let my target activity listen to ACTION_VIEW intents, and specifically, those with the scheme com.package.name
<intent-filter>
<category android:name="android.intent.category.DEFAULT" />
<action android:name="android.intent.action.VIEW" />
<data android:sch...
What is recursion and when should I use it?
...sion.
To see why, walk through the steps that the above languages use to call a function:
space is carved out on the stack for the function's arguments and local variables
the function's arguments are copied into this new space
control jumps to the function
the function's code runs
the function's...
JavaScript closures vs. anonymous functions
...ing what is a closure in JS and what isn't. We just want to make sure we really understand it correctly.
12 Answers
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