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Where do gems install?
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216
Look at your gem environment.
In a terminal run gem env
You should see an entry INSTALLATION...
How to test if list element exists?
...to check that the name is actually defined in the list:
foo <- list(a=42, b=NULL)
foo
is.null(foo[["a"]]) # FALSE
is.null(foo[["b"]]) # TRUE, but the element "exists"...
is.null(foo[["c"]]) # TRUE
"a" %in% names(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["...
C++ include and import difference
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Head GeekHead Geek
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Custom error pages on asp.net MVC3
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201
Here's an example of how I handle custom errors. I define an ErrorsController with actions han...
Why is the .bss segment required?
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answered Mar 2 '12 at 15:11
LundinLundin
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Install an apk file from command prompt?
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723
You can use the code below to install application from command line
adb install example.apk
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
...ese are legal:
h = { :$in => array }
h = { :'a.b' => 'c' }
h[:s] = 42
but these are not:
h = { $in: array }
h = { 'a.b': 'c' } # but this is okay in Ruby2.2+
h[s:] = 42
You can also use anything as a key with => so you can do this:
h = { C.new => 11 }
h = { 23 => 'pancakes hous...
Will the base class constructor be automatically called?
Would the age of customer be 2? It seems like the base class's constructor will be called no matter what. If so, why do we need to call base at the end sometimes?
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Can you do greater than comparison on a date in a Rails 3 search?
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227
Note.
where(:user_id => current_user.id, :notetype => p[:note_type]).
where("date &g...