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When to wrap quotes around a shell variable?
... a numeric value. Whether $URL needs it depends on what you allow in there and whether you still want an argument if it's empty.
I tend to always quote strings just out of habit since it's safer that way.
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Insert, on duplicate update in PostgreSQL?
...mple 38-2. Exceptions with UPDATE/INSERT
This example uses exception handling to perform either UPDATE or INSERT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key...
Logout: GET or POST?
...use GET or POST in general; it is about which is the recommended one for handling logging out of a web application. I have found plenty of information on the differences between GET and POST in the general sense, but I did not find a definite answer for this particular scenario.
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The type or namespace name does not exist in the namespace 'System.Web.Mvc'
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Clean your solution and then set the property of those files to Copy Local = True.
To set the Copy Local property to True or False
In Solution Explorer, click the Show All Files button to display the References node.
Open the References node...
Copy file or directories recursively in Python
Python seems to have functions for copying files (e.g. shutil.copy ) and functions for copying directories (e.g. shutil.copytree ) but I haven't found any function that handles both. Sure, it's trivial to check whether you want to copy a file or a directory, but it seems like a strange omission.
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Significant new inventions in computing since 1980
...World Wide Web ("distributed hypertext via simple mechanisms") as proposed and implemented by Tim Berners-Lee started in 1989/90.
While the idea of hypertext had existed before (Nelson’s Xanadu had tried to implement a distributed scheme), the WWW was a new approach for implementing a distribute...
Is there an easy way to pickle a python function (or otherwise serialize its code)?
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You could serialise the function bytecode and then reconstruct it on the caller. The marshal module can be used to serialise code objects, which can then be reassembled into a function. ie:
import marshal
def foo(x): return x*x
code_string = marshal.dumps(foo.func...
What's valid and what's not in a URI query?
I've been Googling this back and forth reading RFCs and SO questions trying to crack this, but I still don't got jack.
7 An...
HTML 5: Is it , , or ?
...atibility with XHTML; to make it possible to write the same code as XHTML, and have it also work as HTML. Some systems that generate HTML may be based on XML generators, and thus do not have the ability to output just a bare <br> tag; if you're using such a system, it's fine to use <br/>...
Regular expression to match a line that doesn't contain a word
I know it's possible to match a word and then reverse the matches using other tools (e.g. grep -v ). However, is it possible to match lines that do not contain a specific word, e.g. hede , using a regular expression?
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