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Is there a “goto” statement in bash?
...bitrary loops, most require that to be expressed statically -- e.g., break foo; will break out of the loop labeled foo -- whereas in Bash it's expressed dynamically -- e.g., break "$foo" will break out of $foo loops.)
– ruakh
Apr 28 '14 at 16:37
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When is -XAllowAmbiguousTypes appropriate?
...he other:
{-# LANGUAGE FlexibleInstances, OverlappingInstances #-}
class Foo a where
whichOne :: a -> String
instance Foo a where
whichOne _ = "a"
instance Foo [a] where
whichOne _ = "[a]"
-- |
-- >>> main
-- [a]
main :: IO ()
main = putStrLn $ whichOne (undefined :: [Int])
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Assigning default values to shell variables with a single command in bash
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Very close to what you posted, actually:
FOO=${VARIABLE:-default} # If variable not set or null, use default.
Or, which will assign default to VARIABLE as well:
FOO=${VARIABLE:=default} # If variable not set or null, set it to default.
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What is the proper way to check for existence of variable in an EJS template (using ExpressJS)?
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The same way you would do it with anything in js, typeof foo == 'undefined', or since "locals" is the name of the object containing them, you can do if (locals.foo). It's just raw js :p
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In R, how to get an object's name after it is sent to a function?
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Note that for print methods the behavior can be different.
print.foo=function(x){ print(deparse(substitute(x))) }
test = list(a=1, b=2)
class(test)="foo"
#this shows "test" as expected
print(test)
#this (just typing 'test' on the R command line)
test
#shows
#"structure(list(a = 1, b = 2),...
jQuery - Create hidden form element on the fly
...r second question:
$('<input>').attr({
type: 'hidden',
id: 'foo',
name: 'bar'
}).appendTo('form');
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How can you do anything useful without mutable state?
...filesystem every time they modify it with filesystem2 = write(filesystem1, fd, pos, "string"), and let all processes exchange their reference to the filesystem, we could get a much cleaner picture of the operating system.
– eel ghEEz
Jan 22 '15 at 21:21
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PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
... the new value.
So loop 1, the value and $arr[2] become $arr[0], which is 'foo'.
Loop 2, the value and $arr[2] become $arr[1], which is 'bar'.
Loop 3, the value and $arr[2] become $arr[2], which is 'bar' (because of loop 2).
The value 'baz' is actually lost at the first call of the second foreach lo...
How to implement Enums in Ruby?
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Two ways. Symbols (:foo notation) or constants (FOO notation).
Symbols are appropriate when you want to enhance readability without littering code with literal strings.
postal_code[:minnesota] = "MN"
postal_code[:new_york] = "NY"
Constants a...
Using querySelectorAll to retrieve direct children
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let myDiv = getElementById("myDiv");
myDiv.querySelectorAll(":scope > .foo");
Note that in some cases you can also skip .querySelectorAll and use other good old-fashioned DOM API features. For example, instead of myDiv.querySelectorAll(":scope > *") you could just write myDiv.children, for...