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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
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You can slice it:
new_list = old_list[:]
Alex Martelli's opinion (at least back in 2007) about this is, that it is a weird syntax and it does not make sense to use it ever. ;) (In his opinion, the next one is more readable).
You can use the built in list() function:
new_list = list(old_list)
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Why should text files end with a newline?
...essing the last line of a file if it isn't newline terminated.
There's at least one hard advantage to this guideline when working on a terminal emulator: All Unix tools expect this convention and work with it. For instance, when concatenating files with cat, a file terminated by newline will have a...
Can C++ code be valid in both C++03 and C++11 but do different things?
...l, #1 behaviour is unspecified, so i'd count it as undefined behaviour (at least you cannot expect to get a specific result with c++03, now with c++11 you can), #5 uses a non-standard extension of c++. But I guess you're right. The more you look for it, the more examples you'll find which are define...
How come an array's address is equal to its value in C?
...hemeral rvalue (eg. given int a;, it is just like a + 1) - conceptually at least it is "calculated as needed". The real "value" of my_array is the contents of the entire array - it is just that pinning down this value in C is like trying to catch fog in a jar.
– caf
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What exactly is metaprogramming?
...in that code
is there because it has to be. What
that means is that at least 20-25% of
the code in this program is doing
things that you can't easily do in any
other language. However skeptical the
Blub programmer might be about my
claims for the mysterious powers of
Lisp, this ought...
Possible to do a MySQL foreign key to one of two possible tables?
...blem I have three tables; regions, countries, states. Countries can be inside of regions, states can be inside of regions. Regions are the top of the food chain.
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jQuery - Add ID instead of Class
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Try this:
$('element').attr('id', 'value');
So it becomes;
$(function() {
$('span .breadcrumb').each(function(){
$('#nav').attr('id', $(this).text());
$('#container').attr('id', $(this).text());
$('.stretch_footer').attr('i...
Stop Mongoose from creating _id property for sub-document array items
If you have subdocument arrays, Mongoose automatically creates ids for each one. Example:
6 Answers
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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
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SELECT
*
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY section_id ORDER BY name) AS r,
t.*
FROM
xxx t) x
WHERE
x.r <= 2;
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Can an html element have multiple ids?
I understand that an id must be unique within an HTML/XHTML page.
18 Answers
18
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