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Sleep until a specific time/date
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Thanks for that, I wrote a small shell-script to get a "sleepuntil" command.
– theomega
Mar 14 '09 at 15:20
1
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Is using a lot of static methods a bad thing?
I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be ...
Why does “_” (underscore) match “-” (hyphen)?
...you are in a pattern context. e.g. inside a LIKE statement. When replacing all _ with an - : UPDATE sys_file set identifier = REPLACE(identifier, '_', '-') WHERE identifier LIKE '%\_%';. Notice the escaping inside LIKE and no escaping inside REPLACE. (I find it strange though that you are not in a p...
Macro vs Function in C
...uct webpage page;
page.numButtons = 2;
num_button_holes(page) -> 8
Finally, macros can be difficult to debug, producing weird syntax errors or runtime errors that you have to expand to understand (e.g. with gcc -E), because debuggers cannot step through macros, as in this example:
#define prin...
What is your preferred style for naming variables in R? [closed]
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Good previous answers so just a little to add here:
underscores are really annoying for ESS users; given that ESS is pretty widely used you won't see many underscores in code authored by ESS users (and that set includes a bunch of R Core as well as CRAN authors, excptions like Hadley notwithsta...
How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
Why are unnamed namespaces used and what are their benefits?
...ng directive already took place.
This means you can have free functions called (for example) help that can exist in multiple translation units, and they won't clash at link time. The effect is almost identical to using the static keyword used in C which you can put in in the declaration of identif...
How to write header row with csv.DictWriter?
...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...
Get IP address of visitors using Flask for Python
...emote_addr)
When proxies, such as nginx, forward addresses, they typically include the original IP somewhere in the request headers.
Update See the flask-security implementation. Again, review the documentation about ProxyFix before implementing. Your solution may vary based on your particular...
How to set Python's default version to 3.x on OS X?
...n use command python, which will leaving the alias untouched, and works in all shells.
If you launch interpreters more often (I do), you can always create more aliases to add as well, i.e.:
alias 2='python2'
alias 3='python3'
Tip: For scripts, instead of using a shebang like:
#!/usr/bin/env p...