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Django Forms: if not valid, show form with error message
...ee. I return the same form that I got in. The error messages have automatically been added to it by the is_valid() function.
– user984003
Feb 1 '13 at 13:57
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What is the difference between gsub and sub methods for Ruby Strings
...ticed before. I've been using :gsub and it appears that they are essentially the same. Can anyone explain the difference to me? Thanks!
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What character encoding should I use for a HTTP header?
...com/ for more info) for a Server HTTP-header and am wondering if it is "allowed" per spec.
2 Answers
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How to create a multi-tenant database with shared table structures?
Our software currently runs on MySQL. The data of all tenants is stored in the same schema. Since we are using Ruby on Rails we can easily determine which data belongs to which tenant. However there are some companies of course who fear that their data might be compromised, so we are evaluating othe...
Getting the last element of a list
...ist[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down to some_list[-len(some_list)], which gives you the first element.
You can also set list elements in this way. For instance:
>>> some_list = [1, 2, 3]
>>> some_list[-1] = 5 # Set the last e...
Understanding Canvas and Surface concepts
...nders these to the final display in their correct Z-order. A surface typically has more than one buffer (usually two) to do double-buffered rendering: the application can be drawing its next UI state while the surface flinger is compositing the screen using the last buffer, without needing to wait ...
How to keep Maven profiles which are activeByDefault active even if another profile gets activated?
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Because the profile is active automatically when the flag is not there. The profile firstProfile is disabled only if you specify -DskipFirstProfile (eg mvn verify -DskipFirstProfile).
– seanf
Jun 28 '17 at 4:08
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What is the optimal Jewish toenail cutting algorithm?
I am working on the software for a machine that will automatically trim toenails, so that users can simply put their feet in it and run it instead of having to manually do it by biting them or using nail clippers.
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How can I discard remote changes and mark a file as “resolved”?
...ges causing conflicts. Is there a command I can use to in effect say "mark all conflicts as resolved, use local"?
2 Answers...
What does |= (single pipe equal) and &=(single ampersand equal) mean
...icit cast, and the target variable is only evaluated once, but that's basically the gist of it.
In terms of the non-compound operators, & is a bitwise "AND" and | is a bitwise "OR".
EDIT: In this case you want Folder.Attributes &= ~FileAttributes.System. To understand why:
~FileAttribute...