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How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails
...STINCT(*)", :conditions => ["date > #{self.date}"], :limit => 1, :order => 'date', :group => "date").show_generated_sql and have this call the construct_finder_sql method.
– rswolff
Aug 28 '09 at 17:02
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What are -moz- and -webkit-? [duplicate]
...operties to be set specific to each individual browser/rendering engine in order for inconsistencies between implementations to be safely accounted for. The prefixes will, over time, be removed (at least in theory) as the unprefixed, the final version, of the property is implemented in that browser....
Check whether an array is a subset of another
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A list maintains its order but a set does not. If the order is important this would give incorrect results.
– UuDdLrLrSs
Jun 13 '18 at 20:02
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How to output only captured groups with sed?
... groups and their back references. The back references are numbered in the order the groups appear, but they can be used in any order and can be repeated:
echo "foobarbaz" | sed -r 's/^foo(.*)b(.)z$/\2 \1 \2/'
outputs "a bar a".
If you have GNU grep (it may also work in BSD, including OS X):
ec...
Concept behind these four lines of tricky C code
...we're going to do (roughly) like the original, and print it out in reverse order, we'll start by putting it in in reverse order. For our first step, we'll just view that bit pattern as a double, and print out the result:
#include <stdio.h>
char string[] = "skcoR++C";
int main(){
printf(...
How to iterate over a TreeMap? [duplicate]
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will this give out the values ordered?
– phil294
Sep 26 '16 at 23:51
1
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Extract every nth element of a vector
... An advantage of this approach is it can be used on a temporary; in order to use seq you have to be able to call length on the vector. letters[letters < 'm'][c(TRUE, FALSE, FALSE)]
– Matt Chambers
Sep 14 '17 at 21:07
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Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
17
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In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
Why does the expression 0 < 0 == 0 return False in Python?
...o say 0 < x <= 5 than to say (0 < x) and (x <= 5).
These are called chained comparisons. And that's a link to the documentation for them.
With the other cases you talk about, the parenthesis force one relational operator to be applied before the other, and so they are no longer chained...