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Javascript: How to loop through ALL DOM elements on a page?
... nice, but how can I select an element in the upper method? I only got the index 'i'?
– Florian Müller
Nov 23 '10 at 13:35
2
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Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
...
MySQL: Can't create table (errno: 150)
...cing it. It must have the correct column names and types, and it must have indexes on the referenced keys, as stated earlier. If these are not satisfied, MySQL returns Error 1005 and refers to Error 150 in the error message, which means that a foreign key constraint was not correctly formed. Similar...
Can I grep only the first n lines of a file?
...
awk '{ if ( NR <= 10 ) { if(index($0,"ab") > 0) { print $0; } } else { exit; } }' textfile -- faster.
– user982733
Jan 7 '12 at 3:07
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Using python's eval() vs. ast.literal_eval()?
...
datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
How to get sp_executesql result into a variable?
...lah'
SSMS will show this
Msg 2727, Level 11, State 1, Line 1
Cannot find index 'NonExistantStaticsName'.
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How do I add a placeholder on a CharField in Django?
...
Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...
How to make a chain of function decorators?
...her object
scream = shout
# Notice we don't use parentheses: we are not calling the function,
# we are putting the function "shout" into the variable "scream".
# It means you can then call "shout" from "scream":
print(scream())
# outputs : 'Yes!'
# More than that, it means you can remove the old...