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How do I get the number of elements in a list?
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items.append("apple")
items.append("orange")
items.append("banana")
And now:
len(items)
returns 3.
Explanation
Everything in Python is an object, including lists. All objects have a header of some sort in the C implementation.
Lists and other similar builtin objects with a "size" in Python...
onKeyPress Vs. onKeyUp and onKeyDown
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This is of critical importance if you are doing something that relies on knowing the new value after the input rather than the current value such as inline validation or auto tabbing.
Scenario:
The user types 12345 into an input element.
The user selects the text 12345.
The user types the letter...
iOS multiline label in Interface builder
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Ok, I got it now, increased the height, that made it. Thanks!
– Samuli Lehtonen
Jul 2 '11 at 14:38
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What is __stdcall?
... calling you (as is the case here with WinMain). If the compiler doesn't know the correct calling convention then you will likely get very strange crashes as the stack will not be managed correctly.
share
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C# pattern to prevent an event handler hooked twice [duplicate]
...ed from the public event to the private delegate, e.g. Foo?.Invoke() would now become foo?.Invoke(). Otherwise you get an error.
– toddmo
Oct 19 '17 at 16:19
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postgres default timezone
...ement with my database name and SELECT pg_reload_conf() returned true, but now() and select current_setting('TIMEZONE') continue to return values for 'America/New_York'. Is it because I'm not superuser?
– Noumenon
Jul 23 '19 at 4:12
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How to sort an array in Bash
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Now, with the IFS, it splits your elements into little pieces if they have only one particular kind of whitespace in it. Good; not perfect :-)
– Limited Atonement
Jan 29 '16 at 14:56
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What is the difference between map and flatMap and a good use case for each?
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res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For example, it maps from two lines into two line-lengths:
rdd.map(_.length).collect
res1: Array[Int] = Array(13, 16)
But flatMap (loosely speaking...
Permission denied on accessing host directory in Docker
... is empty and the container is created with the named volume.
MacOS users now have OSXFS which handles uid/gid's automatically between the Mac host and containers. One place it doesn't help with are files from inside the embedded VM that get mounted into the container, like /var/lib/docker.sock.
F...
Java equivalent to #region in C#
...s. Seriously no hard feeling here, We are all here to learn and share our knowledge and am stating the fact that I was mislead by your answer, maybe it was a good one back in 2010 but not today. I hope you get my point.
– Mazen Elkashef
Mar 1 '16 at 17:02
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