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Resolve build errors due to circular dependency amongst classes
...ember that the .cc and not the .h is the unit of compilation), you need to allocate space for object A. So, well, how much space then? Enough to store B! What's the size of B then? Enough to store A! Oops.
Clearly a circular reference that you must break.
You can break it by allowing the compiler ...
Transpose a data frame
...You'd better not transpose the data.frame while the name column is in it - all numeric values will then be turned into strings!
Here's a solution that keeps numbers as numbers:
# first remember the names
n <- df.aree$name
# transpose all but the first column (name)
df.aree <- as.data.frame(...
Simple logical operators in Bash
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What you've written actually almost works (it would work if all the variables were numbers), but it's not an idiomatic way at all.
(…) parentheses indicate a subshell. What's inside them isn't an expression like in many other languages. It's a l...
How to do a newline in output
How do I make \n actually work in my output? At the moment it just writes it all in 1 long block. Thanks for any help
4 A...
How to use enum values in f:selectItem(s)
...list was large? And could I do this better? And is it possible to automatically "select" the item that the question have?
4...
How to get the host name of the current machine as defined in the Ansible hosts file?
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The necessary variable is inventory_hostname.
- name: Install this only for local dev machine
pip: name=pyramid
when: inventory_hostname == "local"
It is somewhat hidden in the documentation at the bottom of this section.
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Remove all special characters from a string [duplicate]
...le to convert titles that could contain anything and have them stripped of all special characters so they only have letters and numbers and of course I would like to replace spaces with hyphens.
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Adding Xcode Workspace Schemes to Version Control
...ce Schemes that I've created with the other team members. However they are all stored under .xcodeproj > xcuserdata > .xcuserdatad > xcschemes. I've set xcuserdata folders to be ignore in SVN as I assumed all data in that folder were user specific.
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Node.js - use of module.exports as a constructor
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CommonJS modules allow two ways to define exported properties. In either case you are returning an Object/Function. Because functions are first class citizens in JavaScript they to can act just like Objects (technically they are Objects). Tha...
Push Notifications in Android Platform
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You can generally get activated very quickly, and it is being used for things like GMail so is know to work in production. Unfortunately their sample code for communicating with the server side aspect of C2DM is lacking. I've written up a...