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Why is it slower to iterate over a small string than a small list?
... just
9 LOAD_CONST 6 (('a', 'b', 'c'))
as tuples are immutable. Test:
>>> python3 -m timeit '[x for x in ("a", "b", "c")]'
1000000 loops, best of 3: 0.369 usec per loop
Great, back up to speed.
For Python 2:
def list_iterate():
[item for item in ["a", "b", "c"]]
...
lexers vs parsers
...se is to use "context-free" grammars
and add hacks to the parsers ("symbol tables", etc.) to handle the context-sensitive part.
Neither lexing nor parsing technology is likely to go away soon.
They may be unified by deciding to use "parsing" technology to recognize "words", as is currently explore...
Move assignment operator and `if (this != &rhs)`
...nd is a test-and-branch. Both work. Both meet all of the requirements of Table 22 MoveAssignable requirements in the C++11 standard. The third also works modulo the non-memory-resource-concern.
All three implementations can have different costs depending on the hardware: How expensive is a bran...
C++ performance vs. Java/C#
...) in C# without tremendous work, while it's a built-in feature of C++. Immutable data is an interesting solution, but not everything can be made immutable, so it's not even enough, by far).
So, C# remains an pleasant language as long as you want something that works, but a frustrating language the...
A monad is just a monoid in the category of endofunctors, what's the problem?
...noid in monoidal category" comes later in the book as you can see from the table of contents. And yet understanding this notion is absolutely critical to understanding the connection with monads.
(Strict) monoidal categories
Going to Chapter VII on Monoids (which comes later than Chapter VI on Mon...
Objective-C categories in static library
...lass or category. While
this option will typically result in a
larger executable (due to additional
object code loaded into the
application), it will allow the
successful creation of effective
Objective-C static libraries that
contain categories on existing
classes.
and there is also recommendation...
How to become an OpenCart guru? [closed]
...n using
$result = $this->db->query("SELECT * FROM `" . DB_PREFIX . "table`");
DB_PREFIX as the name suggests is a constant containing the database prefix if one exists
$result will return an object for SELECT queries, containing a few properties
$result->row contains the first row's da...
What are the most interesting equivalences arising from the Curry-Howard Isomorphism?
... have a few things (assisted by the Wikipedia article, which has some neat tables and such itself):
I think that sum types/union types (e.g. data Either a b = Left a | Right b) are equivalent to inclusive disjunction. And, though I'm not very well acquainted with Curry-Howard, I think this demons...
How to implement classic sorting algorithms in modern C++?
...td::not1 around a function object.
C++ Style
There is no generally acceptable C++14 style yet. For better or for worse, I closely follow Scott Meyers's draft Effective Modern C++ and Herb Sutter's revamped GotW. I use the following style recommendations:
Herb Sutter's "Almost Always Auto" and S...
What is a reasonable code coverage % for unit tests (and why)? [closed]
...o less!” Replied the master in a stern voice,
pounding his fist on the table.
The third programmer smiled, bowed,
and left.
...
After this last reply, a young
apprentice approached the great
master:
“Great master, today I overheard you answer the same question about
...