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Print a list in reverse order with range()?
... in general but it accepts range. Why would reversed(range(10000)) need to allocate memory for the whole list? range can return an object that implements the __reversed__ method that allows efficient reverse iteration?
– avmohan
Aug 5 '17 at 10:45
...
How Big can a Python List Get?
... at the end) . Pointers are 4 bytes long and store a memory address to the allocated object. They are "only" 4 bytes long because with 4 bytes you can address every element in a memory of nowadays computers.
– Antonio Ragagnin
Dec 2 '15 at 16:17
...
Laravel orderBy on a relationship
...
It is possible to extend the relation with query functions:
<?php
public function comments()
{
return $this->hasMany('Comment')->orderBy('column');
}
[edit after comment]
<?php
class User
{
public function comments()
{
return $this->hasMany('Comment');...
Accessing Session Using ASP.NET Web API
...r, there is a way to define the session state behavior per route using DataTokens: stackoverflow.com/a/34727708/1412787
– Axel Wilczek
Jan 11 '16 at 17:44
...
When is CRC more appropriate to use than MD5/SHA1?
...
I ran every line of this PHP code in 1.000.000 loop. Results are in comments (#).
hash('crc32', 'The quick brown fox jumped over the lazy dog.');# 750ms 8 chars
hash('crc32b','The quick brown fox jumped over the lazy dog.');# 700ms 8 chars
has...
Can enums be subclassed to add new elements?
...e_StatusGroup.START),
SUCCESS (State_StatusGroup.FINISH),
FAIL_TOKEN_TIMEOUT (State_StatusGroup.FAIL,
State_StatusGroup.FINISH),
FAIL_NOT_COMPLETE (State_StatusGroup.FAIL,
State_StatusGroup.STEP),
FAIL_UNKNOWN (State_StatusGr...
How do I generate a stream from a string?
... This is very compact syntax but it's going to cause a lot of allocations of byte[] so beware in high performance code.
– michael.aird
Mar 19 '17 at 19:08
1
...
Create RegExps on the fly using string variables
...placement with ^ certainly doesn't this, because ^ means a start-of-string token, not a negation. ^ is only a negation in [] character groups. There are also negative lookaheads (?!...), but there are problems with that in JScript so you should generally avoid it.
You might try matching ‘everythi...
Fastest method to escape HTML tags as HTML entities?
... makes my system run out of RAM (with ~6GB free) and firefox seems to stop allocating just before it's out of memory so instead of killing the offending process, linux will sit there and let you do a hard power off.
– Luc
Jul 11 at 9:09
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What are all the common ways to read a file in Ruby?
...asuring in gigabytes, and your host is freezing up as it tries to read and allocate memory.
Line-by-line I/O is very fast, and almost always as effective as slurping. It's surprisingly fast actually.
I like to use:
IO.foreach("testfile") {|x| print "GOT ", x }
or
File.foreach('testfile') {|x|...