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How does Django's Meta class work?
...figuration stuff, there is nothing to stop you changing it:
In [1]: class Foo(object):
...: class Meta:
...: metaVal = 1
...:
In [2]: f1 = Foo()
In [3]: f2 = Foo()
In [4]: f1.Meta.metaVal
Out[4]: 1
In [5]: f2.Meta.metaVal = 2
In [6]: f1.Meta.metaVal
Out[6]: 2
In [7]: F...
how to prevent “directory already exists error” in a makefile when using mkdir
...e is a good way to do it:
OBJDIR := objdir
OBJS := $(addprefix $(OBJDIR)/,foo.o bar.o baz.o)
$(OBJDIR)/%.o : %.c
$(COMPILE.c) $(OUTPUT_OPTION) $<
all: $(OBJS)
$(OBJS): | $(OBJDIR)
$(OBJDIR):
mkdir -p $(OBJDIR)
You should see here the usage of the | pipe operator, defining an order ...
Git for beginners: The definitive practical guide
...t that you asked that we not "simply" link to other resources, it's pretty foolish when there already exists a community grown (and growing) resource that's really quite good: the Git Community Book. Seriously, this 20+ questions in a question is going to be anything but concise and consistent. Th...
jQuery vs document.querySelectorAll
...ave to be disciplined to not write jQuery like this:
$('ul.first').find('.foo').css('background-color', 'red').end().find('.bar').css('background-color', 'green').end();
This is extremely hard to read, while the latter is pretty clear:
$('ul.first')
.find('.foo')
.css('background-color'...
Auto-loading lib files in Rails 4
...ls.root.join('lib')
and keep the right naming convention in lib.
in lib/foo.rb:
class Foo
end
in lib/foo/bar.rb:
class Foo::Bar
end
if you really wanna do some monkey patches in file like lib/extensions.rb, you may manually require it:
in config/initializers/require.rb:
require "#{Rails.ro...
What is the “double tilde” (~~) operator in JavaScript? [duplicate]
... Right. It's primarily a stylistic choice, like the choice between Boolean(foo), (foo ? true : false), or !!foo when you want to cast a variable to a boolean.
– Patrick Fisher
Mar 17 '13 at 8:35
...
How do I get the path to the current script with Node.js?
...Current directory is a very different thing. If you run something like cd /foo; node bar/test.js, current directory would be /foo, but the script is located in /foo/bar/test.js.
– rjmunro
Jul 5 '18 at 11:20
...
Convert Python dict into a dataframe
........
u'2012-07-05': 392,
u'2012-07-06': 392}, orient='index', columns=['foo'])
Out[7]:
foo
2012-06-08 388
2012-06-09 388
2012-06-10 388
2012-06-11 389
2012-06-12 389
........
2012-07-05 392
2012-07-06 392
...
How do I initialize the base (super) class?
...:
def __init__(self):
super(Y, self).__init__(123)
def doit(self, foo):
return super(Y, self).doit(foo)
Because python knows about old- and new-style classes, there are different ways to invoke a base method, which is why you've found multiple ways of doing so.
For completeness sake,...
How to tell Jackson to ignore a field during serialization if its value is null?
...onInclusion(Include.NON_NULL);
or:
@JsonInclude(Include.NON_NULL)
class Foo
{
String bar;
}
Alternatively, you could use @JsonInclude in a getter so that the attribute would be shown if the value is not null.
A more complete example is available in my answer to How to prevent null values ins...