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Node.js: printing to console without a trailing newline?
...ered May 27 '11 at 20:51
onteria_onteria_
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Extracting numbers from vectors of strings
...ion is an indirect way of getting to the solution. If you want to retrieve all the numbers, I recommend gregexpr:
matches <- regmatches(years, gregexpr("[[:digit:]]+", years))
as.numeric(unlist(matches))
If you have multiple matches in a string, this will get all of them. If you're only intere...
Visual Studio can't build due to rc.exe
...exe and rcdll.dll to visual studio 2012\vc\bin or wherever you have it installed:
Part 2: FIX LINK : fatal error LNK1158: cannot run ‘rc.exe’
Add this to your PATH environment variables:
C:\Program Files (x86)\Windows Kits\8.0\bin\x86
Copy these files:
rc.exe
rcdll.dll
From
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What does the “@” symbol mean in reference to lists in Haskell?
...hout the @, you'd have to choose between (1) or (2):(3).
This syntax actually works for any constructor; if you have data Tree a = Tree a [Tree a], then t@(Tree _ kids) gives you access to both the tree and its children.
s...
Equation (expression) parser with precedence?
...ursively, for example, using your sample string,
1+11*5
to do this manually, you would have to read the 1, then see the plus and start a whole new recursive parse "session" starting with 11... and make sure to parse the 11 * 5 into its own factor, yielding a parse tree with 1 + (11 * 5).
This a...
Boost Statechart vs. Meta State Machine
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As there seems to be much interest, please allow me to give my (obviously biased) opinion, which should therefore be taken with a grain of salt:
MSM is much faster
MSM requires no RTTI or anything virtual
MSM has a more complete UML2 support (for example internal tr...
How do PHP sessions work? (not “how are they used?”)
...on files are usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work.
...
Compelling examples of custom C++ allocators?
What are some really good reasons to ditch std::allocator in favor of a custom solution? Have you run across any situations where it was absolutely necessary for correctness, performance, scalability, etc? Any really clever examples?
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How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...cessary instead of DateTime. So use Time.strptime("1318996912345",'%Q').to_f and you will see the milliseconds preserved, while DateTime.strptime("1318996912345",'%Q').to_f does not preserve it.
– skensell
Feb 22 '17 at 15:20
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PostgreSQL create table if not exists
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CREATE TABLE myschema.mytable (i integer);
END IF;
END
$func$;
Call:
SELECT create_mytable(); -- call as many times as you want.
Notes:
The columns schemaname and tablename in pg_tables are case-sensitive. If you double-quote identifiers in the CREATE TABLE statement, you need ...