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querySelector, wildcard element match?
...to do a wildcard element name match using querySelector or querySelectorAll ? I see support for wildcards in attribute queries but not for the elements themselves.
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How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
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Is it possible to make the -init method private in Objective-C?
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Objective-C, like Smalltalk, has no concept of "private" versus "public" methods. Any message can be sent to any object at any time.
What you can do is throw an NSInternalInconsistencyException if your -init method is invoked:
- (id)init {
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How to delete duplicates on a MySQL table?
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The above query deleted all of my records except one :(
– Zolbayar
Aug 10 at 3:21
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Overriding a Rails default_scope
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Short answer: Do not use default_scope unless you really have to. You'll probably be better off with named scopes. With that said, you can use with_exclusive_scope to override the default scope if you need to.
Have a look at this question for more details.
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Setting an environment variable before a command in Bash is not working for the second command in a
In a given shell, normally I'd set a variable or variables and then run a command. Recently I learned about the concept of prepending a variable definition to a command:
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Creating functions in a loop
...have a function that accesses a global variable, like this:
global_var = 'foo'
def my_function():
print(global_var)
global_var = 'bar'
my_function()
When you read this code, you would - of course - expect it to print "bar", not "foo", because the value of global_var has changed after the fu...
How to find where a method is defined at runtime?
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This is really late, but here's how you can find where a method is defined:
http://gist.github.com/76951
# How to find out where a method comes from.
# Learned this from Dave Thomas while teaching Advanced Ruby Studio
# Makes the cas...
Python Remove last 3 characters of a string
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Removing any and all whitespace:
foo = ''.join(foo.split())
Removing last three characters:
foo = foo[:-3]
Converting to capital letters:
foo = foo.upper()
All of that code in one line:
foo = ''.join(foo.split())[:-3].upper()
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Ways to implement data versioning in MongoDB
... approach would be to store diffs. Because the display of these diffs is really a special action, I would put the diffs in a different "history" collection.
I would use the different collection to save memory space. You generally don't want a full history for a simple query. So by keeping the histo...