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What makes Lisp macros so special?
... completely different (e.g. Infix Notation Math for Clojure).
Here is a more concrete example:Python has list comprehensions built into the language. This gives a simple syntax for a common case. The line
divisibleByTwo = [x for x in range(10) if x % 2 == 0]
yields a list containing all even ...
Sharing link on WhatsApp from mobile website (not application) for Android
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Adding 'serial' to existing column in Postgres
... clumsy, if not illegal.
Using the three-parameter form of setval would be more appropriate:
-- vvv
SELECT setval('foo_a_seq', coalesce(max(a), 0) + 1, false) FROM foo;
-- ^ ^
-- ...
What is Normalisation (or Normalization)?
...lly related to redundancy.
Some typical normalization errors:
(1) Having more than one value in a cell. Example:
UserId | Car
---------------------
1 | Toyota
2 | Ford,Cadillac
Here the "Car" column (which is a string) have several values. That offends the first normal form, which say...
Why is there no SortedList in Java?
... list's elements in the internal order of the list (aka. insertion order). More specifically it is in the order you've inserted the elements or on how you've manipulated the list. Sorting can be seen as a manipulation of the data structure, and there are several ways to sort the list.
I'll order th...
Git submodule update
...ying the sub-directory, and vice-versa), then it would be a "submodule" no more, but a subtree merge (also presented in the question Transferring legacy code base from cvs to distributed repository), linking the history of the two Git repo together.
Does that help understanding the true nature of G...
How to break a line of chained methods in Python?
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I also like it best. Doesn't add more code and it's without backslashes.
– Juliusz Gonera
Jan 22 '11 at 23:17
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Using global variables between files?
... way, you achieve your objective while avoid initializing global variables more than once.
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