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Do sealed classes really offer performance Benefits?
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The JITter will sometimes use non-virtual calls to methods in sealed classes since there is no way they can be extended further.
There are complex rules regarding calling type, virtual/nonvirtual, and I don't know them all so I can't really outline them for you, but ...
os.walk without digging into directories below
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Does this function actually "walk" through the whole structure and then delete the entries below a certain point? Or is something more clever going on? I'm not even sure how to check this with code. --python beginner
– mathtic...
C# 4.0 optional out/ref arguments
Does C# 4.0 allow optional out or ref arguments?
9 Answers
9
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When to use symbols instead of strings in Ruby?
...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are generated dynamically is because of memory concerns.
This question is very common because many programming languages don't h...
Maven dependency for Servlet 3.0 API?
...JSTL 1.2, JSF 2.0, JTA 1.1, JSR-45, JSR-250.
But to my knowledge, nothing allows to say that these APIs won't be distributed separately (in java.net repository or somewhere else). For example (ok, it may a particular case), the JSF 2.0 API is available separately (in the java.net repository):
<...
Why aren't variables declared in “try” in scope in “catch” or “finally”?
...Reader sr,
[1] class [mscorlib]System.Exception ex)
IL_0000: ldnull
IL_0001: stloc.0
.try
{
.try
{
IL_0002: ldsfld string UsingTest.Class1::path
IL_0007: newobj instance void [mscorlib]System.IO.StreamReader::.cto...
Best practices for adding .gitignore file for Python projects? [closed]
...uildout I have following in .gitignore (along with *.pyo and *.pyc):
.installed.cfg
bin
develop-eggs
dist
downloads
eggs
parts
src/*.egg-info
lib
lib64
Thanks to Jacob Kaplan-Moss
Also I tend to put .svn in since we use several SCM-s where I work.
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Select first row in each GROUP BY group?
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On Oracle 9.2+ (not 8i+ as originally stated), SQL Server 2005+, PostgreSQL 8.4+, DB2, Firebird 3.0+, Teradata, Sybase, Vertica:
WITH summary AS (
SELECT p.id,
p.customer,
p.total,
ROW_NUMBER() OVER(PARTITION BY p.cus...
Is there a way to auto expand objects in Chrome Dev Tools?
... SINGLE TIME :) Is there a shortcut or setting to have this done automatically?
13 Answers
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How to extract the n-th elements from a list of tuples?
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@Wayne Werner: Yep. This stuff was all just passive knowledge (I don't often use it) - but it's good to be reminded now and then so you know where / what to look for...
– Daren Thomas
Jul 22 '10 at 13:14
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