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How can Perl's print add a newline by default?
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Perl 6 has the say function that automatically appends \n.
You can also use say in Perl 5.10 or 5.12 if you add
use feature qw(say);
to the beginning of your program. Or you can use Modern::Perl to get this and other features.
See perldoc feature for more detai...
Random strings in Python
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In many cases, random isn't really required. Rather, all you really need is unique.
– Chase Seibert
Jan 8 '10 at 19:48
1
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What does T&& (double ampersand) mean in C++11?
...e in the draft C++11 standard, but are not true for the final one! Specifically, it says at various points that rvalue references can bind to lvalues, which was once true, but was changed.(e.g. int x; int &&rrx = x; no longer compiles in GCC) – drewbarbs Jul 13 '14 at 16:12
The biggest d...
Objective-C: difference between id and void *
... will cause premature reaping of objects if _superPrivateDoNotTouch is actually an object. Don't do that.
attempting to invoke a method on a reference of void * type will barf up a compiler warning.
attempting to invoke a method on an id type will only warn if the method being called has not been d...
Could I change my name and surname in all previous commits?
I would like to change my name, surname and email in my all commits, is it possible?
6 Answers
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SqlDataAdapter vs SqlDataReader
...nnection open until you are finished (don't forget to close it!).
Can typically only be iterated over once
Is not as useful for updating back to the database
On the other hand, it:
Only has one record in memory at a time rather than an entire result set (this can be HUGE)
Is about as fast as you c...
Rotating and spacing axis labels in ggplot2
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Change the last line to
q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1))
By default, the axes are aligned at the center of the text, even when rotated. When you rotate +/- 90 degrees, you usually want it to be aligned at the edge instead:
The image ab...
HTTP GET with request body
...body with a GET request.
Yes. In other words, any HTTP request message is allowed to contain a message body, and thus must parse messages with that in mind. Server semantics for GET, however, are restricted such that a body, if any, has no semantic meaning to the request. The requirements on parsin...
Tools to generate database tables diagram with Postgresql? [closed]
...py -dp postgresql-9.3-1100.jdbc3.jar -s public -noads
You'll need to install graphviz as well if you want graphics (apt-get install graphviz for debian based distros).
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Naming of ID columns in database tables
...e wrong records.
If you would like to use the USING syntax that some dbs allow, you cannot if you use ID.
If you use ID you can easily end up with a mistaken join if you happen to be copying the join syntax (don't tell me that no one ever does this!)and forget to change the alias in the join con...