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Length of generator output [duplicate]

...xecution (including memory consumption), will make you surprised: ``` 1: test_list.py:8: 0.492 KiB gen = (i for i in data*1000); t0 = monotonic(); len(list(gen)) ('list, sec', 1.9684218849870376) 2: test_list_compr.py:8: 0.867 KiB gen = (i for i in data*1000); t0 = monotonic(); len([i for i i...
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How to use if - else structure in a batch file?

... and B) THEN X ELSE Y, but in fact means IF A( IF B THEN X ELSE Y). If the test of A fails, then he whole of the inner if-else will be ignored. As one of the answers mentioned, in this case only one of the tests can succeed so the 'else' is not needed, but of course that only works in this example,...
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Enable access control on simple HTTP server

.../env python3 from http.server import HTTPServer, SimpleHTTPRequestHandler, test import sys class CORSRequestHandler (SimpleHTTPRequestHandler): def end_headers (self): self.send_header('Access-Control-Allow-Origin', '*') SimpleHTTPRequestHandler.end_headers(self) if __name__ ==...
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Why am I getting an OPTIONS request instead of a GET request?

...mport/http://metaward.com/u/ptarjan?jsoncallback=?", function(data) { alert(data); }); It's entirely up to the receiving script to make use of that argument (which doesn't have to be called "jsoncallback"), so in this case the function will never be called. But, since you stated you just wan...
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Abort makefile if variable not set

...abs must precede these lines. Generic solution In case you're going to test many variables, it's worth defining an auxiliary function for that: # Check that given variables are set and all have non-empty values, # die with an error otherwise. # # Params: # 1. Variable name(s) to test. # 2. ...
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jQuery get the location of an element relative to window

...nction(){ var offset = $("#simplebox").offset(); alert("Current position of the box is: (left: " + offset.left + ", top: " + offset.top + ")"); }); #simplebox{ width:150px; height:100px; background: #FBBC09; margin: 150px 10...
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Python Process Pool non-daemonic?

... ourselves anyway. pool.close() pool.join() return result def test(): print("Creating 5 (non-daemon) workers and jobs in main process.") pool = MyPool(5) result = pool.map(work, [randint(1, 5) for x in range(5)]) pool.close() pool.join() print(result) if __nam...
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Python: reload component Y imported with 'from X import Y'?

...visual clues that the name's being looked up, ease of mocking/injecting in tests, ability to reload, ability for a module to change flexibly by redefining some entries, predictable and controllable behavior on serialization and recovery of your data [[e.g. by pickling and unpickling]], and so on, an...
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What's the difference between utf8_general_ci and utf8_unicode_ci?

...ks myself. I created a very simple table with 500,000 rows: CREATE TABLE test( ID INT(11) DEFAULT NULL, Description VARCHAR(20) DEFAULT NULL ) ENGINE = INNODB CHARACTER SET utf8 COLLATE utf8_general_ci; Then I filled it with random data by running this stored procedure: CREATE PROCEDURE ran...
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Select all elements with “data-” attribute without using jQuery

... for (var i in a) if (a.hasOwnProperty(i)) { alert(a[i].getAttribute('data-foo')); } </script> </body> </html> share | ...