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Should Gemfile.lock be included in .gitignore?
I'm sort of new to bundler and the files it generates. I have a copy of a git repo from GitHub that is being contributed to by many people so I was surprised to find that bundler created a file that didn't exist in the repo and wasn't in the .gitignore list.
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CSS opacity only to background color, not the text on it? [duplicate]
...assign the opacity property to the background property of a div only and not to the text on it?
11 Answers
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How to test if list element exists?
...es(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["a"]] is safer than foo$a, since the latter uses partial matching and thus might also match a longer name:
x <- list(abc=4)
x$a # 4, since it partially matches abc
x[["a"]] # NULL, no match
[UPDATE] So, back t...
How to make return key on iPhone make keyboard disappear?
I have two UITextFields (e.g. username and password) but I cannot get rid of the keyboard when pressing the return key on the keyboard. How can I do this?
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Transitions on the CSS display property
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You can concatenate two transitions or more, and visibility is what comes handy this time.
div {
border: 1px solid #eee;
}
div > ul {
visibility: hidden;
opacity: 0;
transition: visibility 0s, opacity 0.5s linear;
}
div:hover > ul {
visibil...
How to check Django version
I have to use Python and Django for our application. So I have two versions of Python, 2.6 and 2.7. Now I have installed Django. I could run the sample application for testing Django succesfuly. But how do I make sure whether Django uses the 2.6 or 2.7 version and what version of modules Django ...
How to loop through a directory recursively to delete files with certain extensions
I need to loop through a directory recursively and remove all files with extension .pdf and .doc . I'm managing to loop through a directory recursively but not managing to filter the files with the above mentioned file extensions.
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How to check if a file contains a specific string using Bash
...ns # SomeString was found
fi
You don't need [[ ]] here. Just run the command directly. Add -q option when you don't need the string displayed when it was found.
The grep command returns 0 or 1 in the exit code depending on
the result of search. 0 if something was found; 1 otherwise.
$ echo hello...
update package.json version automatically
Before I do a small release and tag it, I'd like to update the package.json to reflect the new version of the program.
11 A...
Check if null Boolean is true results in exception
...r null as any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
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