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Can't find the 'libpq-fe.h header when trying to install pg gem
...on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error:
...
Accessing an SQLite Database in Swift
...robably use one of the many SQLite wrappers, if you wanted to know how to call the SQLite library yourself, you would:
Configure your Swift project to handle SQLite C calls. If using Xcode 9 or later, you can simply do:
import SQLite3
Create/open database.
let fileURL = try! FileManager.default...
Extract subset of key-value pairs from Python dictionary object?
...
If you're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
...
.trim() in JavaScript not working in IE
...han.com/archives/faster-trim-javascript
– Daniel Vassallo
Feb 22 '10 at 0:53
92
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How to prevent ifelse() from turning Date objects into numeric objects
...irst this felt a little "hackish" to me. But now I just think of it as a small price to pay for the performance returns that I get from ifelse(). Plus it's still a lot more concise than a loop.
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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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How do you default a new class to public when creating it in Visual Studio?
...1033.
Visual Studio 2010 (10.0) and below: There is a zip file in there called Class.zip. Unpack this, edit the file to put in your public keyword then re-pack it (make sure you backup the original).
After this, make sure VS rebuilds it's cache (which is just the zipfiles unzipped into directorie...
How to search a Git repository by commit message?
...
To search the commit log (across all branches) for the given text:
git log --all --grep='Build 0051'
To search the actual content of commits through a repo's history, use:
git grep 'Build 0051' $(git rev-list --all)
to show all instances of the given t...
How do I create a MongoDB dump of my database?
...ump:
$ ./mongodump --host prod.example.com
connected to: prod.example.com
all dbs
DATABASE: log to dump/log
log.errors to dump/log/errors.bson
713 objects
log.analytics to dump/log/analytics.bson
234810 objects
DATABASE: blog to dump/blog
...
How to check whether a file or directory exists?
...iven file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
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