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What's the use of ob_start() in php?

...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet." For example: ob_start(); echo("Hello there!"); //would normally get printed to the screen/output to browser $output = ob_get_contents(); ob_end_clean(); There a...
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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...
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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 ...
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Can “using” with more than one resource cause a resource leak?

... 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...
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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...
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Hiding elements in responsive layout?

...gh bootstrap it looks like they support collapsing the menubar items for smaller screens. Is there something similar for other items on the page? ...
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Hidden Features of C++? [closed]

...refore, with http://stackoverflow.com, http is a label (you could theoretically write goto http;), and //stackoverflow.com is just an end-of-line comment. Both of these are legal C++, so the construct compiles. It doesn't do anything vaguely useful, of course. – David Thornle...
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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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Using PUT method in HTML form

... XHTML 1.x forms only support GET and POST. GET and POST are the only allowed values for the "method" attribute. share | improve this answer | follow | ...
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How to get line count of a large file cheaply in Python?

... 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 ...