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__proto__ VS. prototype in JavaScript
...that is used to build __proto__ when you create an object with new:
( new Foo ).__proto__ === Foo.prototype;
( new Foo ).prototype === undefined;
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JavaScript null check
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typeof foo === "undefined" is different from foo === undefined, never confuse them. typeof foo === "undefined" is what you really need. Also, use !== in place of !=
So the statement can be written as
function (data) {
if (typeof...
How to pass macro definition from “make” command line arguments (-D) to C source code?
...
Just use a specific variable for that.
$ cat Makefile
all:
echo foo | gcc $(USER_DEFINES) -E -xc -
$ make USER_DEFINES="-Dfoo=one"
echo foo | gcc -Dfoo=one -E -xc -
...
one
$ make USER_DEFINES="-Dfoo=bar"
echo foo | gcc -Dfoo=bar -E -xc -
...
bar
$ make
echo foo | gcc -E -xc -
.....
How to run code when a class is subclassed? [duplicate]
...Classes (by default) are instances of type.
Just as an instance of a class Foo is created by foo = Foo(...),
an instance of type (i.e. a class) is created by myclass = type(name, bases, clsdict).
If you want something special to happen at the moment of class-creation, then you have to modify the th...
How to pipe list of files returned by find command to cat to view all the files
...do what you are wanting to do -- but is specific to find)
find . -name '*.foo' -exec cat {} \;
(Everything between find and -exec are the find predicates you were already using. {} will substitute the particular file you found into the command (cat {} in this case); the \; is to end the -exec co...
Restful way for deleting a bunch of items
...about what we mean with our URL, parameters and REST method.
return all 'foo' elements:
[GET] api/foo
return 'foo' elements with filtering for specific ids:
[GET] api/foo?ids=3,5,9
Wherein the sense is the URL and the filter determine "what elements we are dealing with?", and the REST method (...
Capturing multiple line output into a Bash variable
...actical purposes this is way easier to deal with.
./myscript.sh > /tmp/foo
while read line ; do
echo 'whatever you want to do with $line'
done < /tmp/foo
Quick hack to make it do the requested action:
result=""
./myscript.sh > /tmp/foo
while read line ; do
result="$result$line\n"...
How do I convert a dictionary to a JSON String in C#?
...tring[] args)
{
Dictionary<int, List<int>> foo = new Dictionary<int, List<int>>();
foo.Add(1, new List<int>( new int[] { 1, 2, 3, 4 }));
foo.Add(2, new List<int>(new int[] { 2, 3, 4, 1 }));
foo.Add(3, new Li...
Java generics - why is “extends T” allowed but not “implements T”?
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To add to the confusion getFoo(List<? super Foo> fooList) ONLY works with the class that literally are extended by Foo like class Foo extends WildcardClass. In this case a List<WildcardClass> would be acceptable input. However any class...
eval command in Bash and its typical uses
...able substitutions and command substitutions (i.e. anytime there's a $): "$foo", "$(foo)". Always put double quotes around variable and command substitutions, unless you know you need to leave them off. Without the double quotes, the shell performs field splitting (i.e. it splits value of the variab...