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How do I determine the target architecture of static library (.a) on Mac OS X?
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244
Another option is lipo; its output is brief and more readable than otool's.
An example:
% li...
What makes Lisp macros so special?
...for a common case. The line
divisibleByTwo = [x for x in range(10) if x % 2 == 0]
yields a list containing all even numbers between 0 and 9. Back in the Python 1.5 days there was no such syntax; you'd use something more like this:
divisibleByTwo = []
for x in range( 10 ):
if x % 2 == 0:
...
What is the fastest or most elegant way to compute a set difference using Javascript arrays?
...if don't know if this is most effective, but perhaps the shortest
A = [1, 2, 3, 4];
B = [1, 3, 4, 7];
diff = A.filter(function(x) { return B.indexOf(x) < 0 })
console.log(diff);
Updated to ES6:
A = [1, 2, 3, 4];
B = [1, 3, 4, 7];
diff = A.filter(x => !B.includes(x) );
console.log(diff)...
How do I parse a URL query parameters, in Javascript? [duplicate]
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2 Answers
2
Active
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Insert, on duplicate update in PostgreSQL?
...ing syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group archives for "upsert" leads to...
Are GUID collisions possible?
I'm working on a database in SQL Server 2000 that uses a GUID for each user that uses the app it's tied to. Somehow, two users ended up with the same GUID. I know that microsoft uses an algorithm to generate a random GUID that has an extremely low chance of causing collisons, but is a collision stil...
Checkout old commit and make it a new commit [duplicate]
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221
git rm -r .
git checkout HEAD~3 .
git commit
After the commit, files in the new HEAD will be...
How to import multiple .csv files at once?
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274
Something like the following should result in each data frame as a separate element in a singl...
Difference between HashMap, LinkedHashMap and TreeMap
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1182
All three classes implement the Map interface and offer mostly the same functionality. The most ...
How to instantiate a File object in JavaScript?
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211
According to the W3C File API specification, the File constructor requires 2 (or 3) parameters...