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When to use ' (or quote) in Lisp?
...nly want to evaluate small parts of the code returned, so the backquote is more suited. For shorter lists, list can be more readable.
Hey, You Forgot About quote!
So, where does this leave us? Oh right, what does quote actually do? It simply returns its argument(s) unevaluated! Remember what I s...
Constantly print Subprocess output while process is running
...he process pauses for a bit without writing anything to stdout there is no more input to read. You will need a loop to check whether or not the process has finished. I tried this using subprocess32 on python 2.7
– Har
Dec 26 '15 at 19:05
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Function overloading by return type?
Why don't more mainstream statically typed languages support function/method overloading by return type? I can't think of any that do. It seems no less useful or reasonable than supporting overload by parameter type. How come it's so much less popular?
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python max function using 'key' and lambda expression
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With a single iterable argument, return its largest item. With two or
more arguments, return the largest argument.
So, it simply returns the object that is the largest.
How does key work?
By default in Python 2 key compares items based on a set of rules based on the type of the objects (f...
Copy all files and folders using msbuild
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Works fine - thank you! I wonder why other more complicated answers have more upvotes?!
– Ivan
Sep 18 '14 at 9:31
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How to change the commit author for one specific commit?
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How to profile a bash shell script slow startup?
...rofiling data), as one doesn't has to untangle stderr and set -x output anymore (so many edge cases).
– pawamoy
Apr 24 '19 at 19:54
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Loop through an array in JavaScript
...o it's safe to use them.
And with the ES6 arrow function syntax, it's even more succinct:
array.forEach(item => console.log(item));
Arrow functions are also widely implemented unless you plan to support ancient platforms (e.g., IE11); you are also safe to go.
Pros
Very short and succinct.
Decla...
Perl build, unit testing, code coverage: A complete working example
...ctiveState ActivePerl v5.10.0 on a Windows XP Pro PC, Module::Build, Test::More, Devel::Cover)
Start out with a directory for your Perl project and then create a "lib" directory and a "t" directory under your project directory:
HelloPerlBuildWorld
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|----------> lib
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MySQL, better to insert NULL or empty string?
...NULL you can distinguish between "put no data" and "put empty data".
Some more differences:
A LENGTH of NULL is NULL, a LENGTH of an empty string is 0.
NULLs are sorted before the empty strings.
COUNT(message) will count empty strings but not NULLs
You can search for an empty string using a bound...