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How can two strings be concatenated?
...paste()
is the way to go. As the previous posters pointed out, paste can do two things:
concatenate values into one "string", e.g.
> paste("Hello", "world", sep=" ")
[1] "Hello world"
where the argument sep specifies the character(s) to be used between the arguments to concatenate,
or colla...
How do you represent a graph in Haskell?
...e Knot to get around this, but that makes my brain hurt (because I haven't done much of it yet). I've done more of my substantial programming in Mercury than Haskell so far, and Mercury is strict so knot-tying doesn't help.
Usually when I've run into this before I've just resorted to additional ind...
How do I migrate a model out of one django app and into a new one?
... it. I realize now that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
...
How do you stop MySQL on a Mac OS install?
...t mysql
brew services stop mysql
brew services restart mysql
MacPorts
sudo port load mysql57-server
sudo port unload mysql57-server
Note: this is persistent after a reboot.
Binary installer
sudo /Library/StartupItems/MySQLCOM/MySQLCOM stop
sudo /Library/StartupItems/MySQLCOM/MySQLCOM start
su...
Can't specify the 'async' modifier on the 'Main' method of a console app
...ations (the method returns off the thread but keeps the request alive). It doesn't work out so well for Console programs: Main returns to the OS - so your program exits.
One solution is to provide your own context - a "main loop" for your console program that is async-compatible.
If you have a mach...
How do I make a checkbox required on an ASP.NET form?
I've done some searching on this, and I've found several partial answers, however nothing that gives me that warm fuzzy "this is the right way to do this". To answer the most frequently occurring complaint against this question: "checkboxes can have two legitimate states - checked and unchecked", th...
Is there a way to get a collection of all the Models in your Rails app?
...swers than this one! Or try to improve this one as community wiki.
Models do not register themselves to a master object, so no, Rails does not have the list of models.
But you could still look in the content of the models directory of your application...
Dir.foreach("#{RAILS_ROOT}/app/models") do...
What is the best way to do a substring in a batch file?
...t names only
To precisely answer your question, however: Substrings are done using the :~start,length notation:
%var:~10,5%
will extract 5 characters from position 10 in the environment variable %var%.
NOTE: The index of the strings is zero based, so the first character is at position 0, the...
How do I remedy “The breakpoint will not currently be hit. No symbols have been loaded for this docu
...ve arrived at a breakpoint or used Debug > Break All, use Debug > Windows > Modules. You'll see a list of all the assemblies that are loaded into the process. Locate the one you want to get debug info for. Right-click it and select Symbol Load Information. You'll get a dialog that lists...
Why do I need Transaction in Hibernate for read-only operations?
Why do I need Transaction in Hibernate for read-only operations?
4 Answers
4
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