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How to check if a specific key is present in a hash or not?
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my_hash2.has_key?("my_key".to_sym)
=> false
But when creating hash if you pass string as key then it will search for the string in keys.
But when creating hash you pass symbol as key then has_key? will search the keys by using symbol.
If you are using Rails, you can use Hash#with_indiffe...
How can I automate the “generate scripts” task in SQL Server Management Studio 2008?
...tionality via the command line like:
sqlpubwiz help script
I don't know if v1.4 has the same troubles that v1.1 did (users are converted to roles, constraints are not created in the right order), but it is not a solution for me because it doesn't script objects to different files like the Tasks-&...
How do you move a commit to the staging area in git?
If you want to move a commit to the staging area - that is uncommit it and move all of the changes which were in it into the staging area (effectively putting the branch in the state that it would have been in prior to the commit) - how do you do it? Or is it something that you can't do?
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SQL how to make null values come last when sorting ascending
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Note however that if you place an index on the sort column to improve performance(*), then this method will somewhat complicate the query plan and lose much of the performance benefit. * - indexes provided the data presorted, hence avoiding a ...
GIT clone repo across local file system in windows
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You can specify the remote’s URL by applying the UNC path to the file protocol. This requires you to use four slashes:
git clone file:////<host>/<share>/<path>
For example, if your main machine has the IP 192.168.1...
Using the Android Application class to persist data
...vity. Based on my findings, the Application class does not have the same life-cycle (i.e. it is, for all intents and purposes, always instantiated). Does it make sense to store the state information inside of the application class and then reference it from the Activity, or is that generally not t...
Is it possible to reference one CSS rule within another?
For example if I have the following HTML:
7 Answers
7
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Break or return from Java 8 stream forEach?
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If you need this, you shouldn't use forEach, but one of the other methods available on streams; which one, depends on what your goal is.
For example, if the goal of this loop is to find the first element which matches some p...
How do I delete an exported environment variable?
...variables you set in one terminal instance will not carry over to another. If you have a variable which seems to be set automatically every time you open terminal, try looking through the various hidden files in your home directory for it. Or, to see where it is being set, try "grep -r <X> ~" ...
Insert line after first match using sed
... about inserting a choice line of text after the first line matching a specific string using the sed command. I have ...
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