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Rails 3 check if attribute changed
Need to check if a block of attributes has changed before update in Rails 3.
5 Answers
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Implementing slicing in __getitem__
...y) and my __getitem__ looks like this:
def __getitem__( self, key ) :
if isinstance( key, slice ) :
#Get the start, stop, and step from the slice
return [self[ii] for ii in xrange(*key.indices(len(self)))]
elif isinstance( key, int ) :
if key < 0 : #Handle negativ...
How to use a variable inside a regular expression?
...nterpolation, "f-strings". In your particular case the solution would be:
if re.search(rf"\b(?=\w){TEXTO}\b(?!\w)", subject, re.IGNORECASE):
...do something
EDIT:
Since there have been some questions in the comment on how to deal with special characters I'd like to extend my answer:
raw str...
mkdir -p functionality in Python [duplicate]
...system call. I am sure the code is less than 20 lines, and I am wondering if someone has already written it?
12 Answers
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How to delete items from a dictionary while iterating over it?
...)) and it should work.
A simple test in the console shows you cannot modify a dictionary while iterating over it:
>>> mydict = {'one': 1, 'two': 2, 'three': 3, 'four': 4}
>>> for k, v in mydict.iteritems():
... if k == 'two':
... del mydict[k]
...
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Clear Text Selection with JavaScript
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if (window.getSelection) {
if (window.getSelection().empty) { // Chrome
window.getSelection().empty();
} else if (window.getSelection().removeAllRanges) { // Firefox
window.getSelection().removeAllRanges();
}
...
Can you have if-then-else logic in SQL? [duplicate]
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You can make the following sql query
IF ((SELECT COUNT(*) FROM table1 WHERE project = 1) > 0)
SELECT product, price FROM table1 WHERE project = 1
ELSE IF ((SELECT COUNT(*) FROM table1 WHERE project = 2) > 0)
SELECT product, price FROM table1 WHER...
Why do we usually use || over |? What is the difference?
...
If you use the || and && forms, rather than the | and & forms of these operators, Java will not bother to evaluate the right-hand operand alone.
It's a matter of if you want to short-circuit the evaluation or not...
How to insert newline in string literal?
... of course but I meant avoiding using Environment.NewLine, my question was if there is '/newline' literal.
– Captain Comic
Nov 3 '10 at 9:46
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Javascript and regex: split string and keep the separator
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I was having similar but slight different problem. Anyway, here are examples of three different scenarios for where to keep the deliminator.
"1、2、3".split("、") == ["1", "2", "3"]
"1、2、3".split(/(、)/g) == ["1", "、", "2", "、", "3"]
"1、2、3"...