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In Ruby, is there an Array method that combines 'select' and 'map'?
... .uniq
.sort
end
The .lazy method returns a lazy enumerator. Calling .select or .map on a lazy enumerator returns another lazy enumerator. Only once you call .uniq does it actually force the enumerator and return an array. So what effectively happens is your .select and .map calls are ...
Why does python use 'else' after for and while loops?
... to seasoned Python coders. When used in conjunction with for-loops it basically means "find some item in the iterable, else if none was found do ...". As in:
found_obj = None
for obj in objects:
if obj.key == search_key:
found_obj = obj
break
else:
print('No object found.')...
CSS horizontal centering of a fixed div?
...creen, even if the page is scrolled it should always stay CENTERED in the middle of the screen!
8 Answers
...
Measure and Benchmark Time for Ruby Methods
...the time measure code:
def measure(&block)
start = Time.now
block.call
Time.now - start
end
# t1 and t2 is the executing time for the code blocks.
t1 = measure { sleep(1) }
t2 = measure do
sleep(2)
end
share
...
Why does the 260 character path length limit exist in Windows?
...PIs. For example, LoadLibrary, which maps a module into the address of the calling process, fails if the file name is longer than MAX_PATH. So this means MoveFile will let you move a DLL to a location such that its path is longer than 260 characters, but when you try to load the DLL, it would fail. ...
Store boolean value in SQLite
...ase specific values e.g.
CREATE TABLE IF NOT EXISTS "boolean_test"
(
"id" INTEGER PRIMARY KEY AUTOINCREMENT
, "boolean" TEXT NOT NULL
CHECK( typeof("boolean") = "text" AND
"boolean" IN ("TRUE","FALSE")
)
);
INSERT INTO "boolean_test" ("boolean") VALUES ("TRUE"...
Can every recursion be converted into iteration?
...s a problem for existing C environments. Another example is the use of lexically nested functions and static scope, which Pascal supports but C doesn't.
In these circumstances, you might try to overcome political resistance to the original language. You might find yourself reimplementing Lisp badly...
How do I scale a stubborn SVG embedded with the tag?
I have some SVG files that specifies width and height as well as viewbox like this:
9 Answers
...
What is the command to exit a Console application in C#?
...late to properly terminate with an exit code so you may be better off just calling Environment.Exit.
Another point against using Evironment.Exit - even when writing multi-threaded applications - is reusability. If you ever want to reuse your code in an environment that makes Environment.Exit irrele...
Run certain code every n seconds [duplicate]
...dard library only, no external dependencies
start() and stop() are safe to call multiple times even if the timer has already started/stopped
function to be called can have positional and named arguments
You can change interval anytime, it will be effective after next run. Same for args, kwargs and e...