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Where to place $PATH variable assertions in zsh?
...'t listed in any zsh documentation I can find.
This turns out to be partially incorrect: /etc/profile may be sourced by zsh. However, this only occurs if zsh is "invoked as sh or ksh"; in these compatibility modes:
The usual zsh startup/shutdown scripts are not executed. Login shells source /e...
Why is there a difference in checking null against a value in VB.NET and C#?
...I don't know yet". Then the comparison of 5 to "I don't know yet". is naturally "I don't know yet"; ie NULL. This has the additional advantage of mirroring the behaviour of NULL in (most if not all) SQL databases. This is also a more standard (than C#'s) interpretation of three-valued logic, as expl...
What is the difference between const and readonly in C#?
...time of a definition for a const VS readonly values can be computed dynamically but need to be assigned before the constructor exits.. after that it is frozen.
'const's are implicitly static. You use a ClassName.ConstantName notation to access them.
There is a subtle difference. Consider a class d...
Tick symbol in HTML/XHTML
...splay a tick symbol (✓ or ✔) within an internal web app and would ideally like to avoid using an image.
14 Answers
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Difference between window.location.href=window.location.href and window.location.reload()
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Also note that location.reload() will also force reload all static content (much like a ctrl+f5 style hard refresh) whereas setting location.href back to href (or pathname or URL) does not, which could be a significant (and unnecessary) difference in load time on some pages.
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MySQL load NULL values from CSV data
...one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
If they're all possibly empty, then you'd read them all into variables and have multiple SET statements, like this:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(@vone, @vtwo, @v...
Haversine Formula in Python (Bearing and Distance between two GPS points)
...fy math.pi, math.sin etc. With from math import * you get direct access to all the module contents. Check out "namespaces" in a python tutorial (such as docs.python.org/tutorial/modules.html)
– Michael Dunn
Feb 6 '11 at 21:20
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Why .NET String is immutable? [duplicate]
As we all know, String is immutable. What are the reasons for String being immutable and the introduction of StringBuilder class as mutable?
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Output array to CSV in Ruby
...enerate_line(row) }.join("")
#=> "a1,a2,a3\nb1,b2,b3\nc1,c2,c3\n"
Do all of the above and save to a csv, in one line.
File.open("ss.csv", "w") {|f| f.write(rows.inject([]) { |csv, row| csv << CSV.generate_line(row) }.join(""))}
NOTE:
To convert an active record database to csv would...
Why can't variables be declared in a switch statement?
...lity and consistency in the code. In the old days, you might have automatically got an "extra" stack frame, but now that should not be the case for any decent optimizing compiler.
– Tall Jeff
Sep 18 '08 at 14:37
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