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What makes Lisp macros so special?
...not had the privilege of using Lisp macros. As someone who wants to understand the buzz, please explain what makes this feature so powerful.
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When should we use mutex and when should we use semaphore
When should we use mutex and when should we use semaphore ?
12 Answers
12
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
What is the difference between == and === in PHP?
11 Answers
11
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OPTION (RECOMPILE) is Always Faster; Why?
...istics. This can be done by running the following:
EXEC sp_updatestats
And then recreating your execution plan. This will ensure that when your execution plan is created it will be using the latest information.
Adding OPTION(RECOMPILE) rebuilds the execution plan every time that your query exe...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
I tested the above code in Chrome's console and for some reason, a() returns true, b() returns true, and c() returns false.
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In Python how should I test if a variable is None, True or False
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Don't fear the Exception! Having your program just log and continue is as easy as:
try:
result = simulate(open("myfile"))
except SimulationException as sim_exc:
print "error parsing stream", sim_exc
else:
if result:
print "result pass"
else:
print...
How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
...here for more details):
Search in Elements panel like below
Execute $x() and $$() in Console panel, as shown in Lawrence's answer
Third party extensions (not really necessary in most of the cases, could be an overkill)
Here is how you search XPath in Elements panel:
Press F12 to open Chrome De...
Generating v5 UUID. What is name and namespace?
I've read the man page, but I do not undestand what name and namespace are for.
3 Answers
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Custom HTTP headers : naming conventions
... posted to deprecate the recommendation of using the "X-" prefix for non-standard headers. The reason is that when non-standard headers prefixed with "X-" become standard, removing the "X-" prefix breaks backwards compatibility, forcing application protocols to support both names (E.g, x-gzip & ...
SQL: IF clause within WHERE clause
...ion in most cases. In my case, I wanted the change the comparison operator and hence I used the next approach.
– Birla
Nov 15 '14 at 11:59
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