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Generator Expressions vs. List Comprehension
...or slicing
print [5,6] + gen() # generators can't be added to lists
Basically, use a generator expression if all you're doing is iterating once. If you want to store and use the generated results, then you're probably better off with a list comprehension.
Since performance is the most common rea...
Standard concise way to copy a file in Java?
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As toolkit mentions above, Apache Commons IO is the way to go, specifically FileUtils.copyFile(); it handles all the heavy lifting for you.
And as a postscript, note that recent versions of FileUtils (such as the 2.0.1 release) have added the use of NIO for copying files; NIO can significantly ...
How to modify existing, unpushed commit messages?
... the most recent commit message
git commit --amend
will open your editor, allowing you to change the commit message of the most recent commit. Additionally, you can set the commit message directly in the command line with:
git commit --amend -m "New commit message"
…however, this can make multi-...
C# declare empty string array
...ew string[5];
That will create arr, a referenced array of strings, where all elements of this array are null. (Since strings are reference types)
This array contains the elements from arr[0] to arr[4]. The new operator is used to create the array and initialize the array elements to their default...
Change Bootstrap tooltip color
...!!! Fixed. @codesnooker didn't see that you were mentioning the arrow!!! Really sorry!!!
– Praveen Kumar Purushothaman
Mar 10 '15 at 10:03
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Difference between database and schema
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A database is the main container, it contains the data and log files, and all the schemas within it. You always back up a database, it is a discrete unit on its own.
Schemas are like folders within a database, and are mainly used to group logical objects together, which leads to ease of setting pe...
Android TextView with Clickable Links: how to capture clicks?
...v this happens with ListViews when a View's focusable is set true. This usually happens with Buttons/ImageButtons. Try calling setFocusable(false) on your TextView.
– Sufian
Sep 11 '14 at 10:59
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How do I escape a reserved word in Oracle?
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Try it in all uppercase "TABLE".
– RSHAP
Aug 14 '18 at 15:42
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How to do two-way filtering in AngularJS?
...ion? Isn't that just a generic controller for the directive that has basically nothing to do with the ngModel attribute? (Still learning angular here so I could be totally wrong.)
– Drew Miller
Dec 17 '12 at 1:52
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Count number of objects in list [closed]
...'s put some stuff in it - 3 components/indexes/tags (whatever you want to call it) each with differing amounts of elements:
> mylist <- list(record1=c(1:10),record2=c(1:5),record3=c(1:2))
If you are interested in just the number of components in a list use:
> length(mylist)
[1] 3
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