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What is a elegant way in Ruby to tell if a variable is a Hash or an Array?
...e is dependent on the ordering of the data(e.g. if you are using each_with_index). The order of the elements is implemented differently between hashes and arrays and it is different between ruby versions.(intertwingly.net/slides/2008/oscon/ruby19/22)
– juan2raid
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Test if a variable is a list or tuple
... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so:
import types
isinstance(var, types.String...
Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
CSS styling in Django forms
...ling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend methods (js, css). I didn't say your answer is wrong. In my opinion its just bad practice (esspecially ...
Can “using” with more than one resource cause a resource leak?
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No.
The compiler will generate a separate finally block for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the...
How to take the first N items from a generator or list in Python? [duplicate]
...imple syntax: array[start:stop:step]
You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step]
Slicing a generator
import itertools
top5 = itertools.islice(my_list, 5) # grab the first five elements
You can't slice a generator directly in Python. itertools.i...
How to rename with prefix/suffix?
...available and you have to rename more than one file, shell scripting can really be short and simple for this. For example, to rename all *.jpg to prefix_*.jpg in the current directory:
for filename in *.jpg; do mv "$filename" "prefix_$filename"; done;
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SearchView's OnCloseListener doesn't work
...ter inflater = getMenuInflater();
inflater.inflate(R.menu.conversation_index_activity_menu, menu);
mSearchView = (SearchView) menu.findItem(R.id.itemSearch).getActionView();
MenuItem menuItem = menu.findItem(R.id.itemSearch);
int currentapiVersion = android.os.Build.VERSION.SDK_IN...
Convert int to char in java
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With this you get the decimal value as a char type. I used charAt() with index 0 because the only value into that String is 'a' and as you know, the position of 'a' into that String start at 0.
Sorry if my english isn't well explained, hope it helps you.
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How to get line count of a large file cheaply in Python?
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You can't get any better than that.
After all, any solution will have to read the entire file, figure out how many \n you have, and return that result.
Do you have a better way of doing that without reading the entire file? Not sure... The best solution will always ...