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Why can't I inherit static classes?
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Other opinions from channel9
Inheritance in .NET works only on instance base. Static methods are defined on the type level not on the instance level. That is why overriding doesn't work with static methods/properties/events...
Static methods are only held once in memory. There is no virtual table...
How to print out the contents of a vector?
...re complicated objects where this solution is not going to be ideal.
range-based for loop (C++11)
See Jefffrey's solution. In C++11 (and later) you can use the new range-based for loop, which looks like this:
for (auto i: path)
std::cout << i << ' ';
Since path is a vector of items (e...
Tool to Unminify / Decompress JavaScript [closed]
...ne only formats the code, it doesn't change variable names, nor uncompress base62 encoding.
edit: in fact it can unpack "packed" scripts (packed with Dean Edward's packer : http://dean.edwards.name/packer/)
share
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Run a callback only if an attribute has changed in Rails
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Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c...
Extracting the last n characters from a string in R
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I'm not aware of anything in base R, but it's straight-forward to make a function to do this using substr and nchar:
x <- "some text in a string"
substrRight <- function(x, n){
substr(x, nchar(x)-n+1, nchar(x))
}
substrRight(x, 6)
[1] "string"...
Can modules have properties the same way that objects can?
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Based on this, I added another answer: stackoverflow.com/a/58526852/2124834
– user2124834
Oct 23 '19 at 15:59
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How can I generate a diff for a single file between two branches in github
...ttps://github.com/owner/repo-name.git
# git@github.com:owner/repo-name.git
BASE_URL="https://github.com/""$(git config --get remote.origin.url | sed 's/.*github\.com[/:]\(.*\).git/\1/')""/compare"
if [[ "$#" -eq 1 ]]; then
if [[ "$1" =~ .*\.\..* ]]; then
# Handle "git hubdiff fromcommit..toco...
Speed up the loop operation in R
... @carbontwelve Ooops, I was wrong :) This are standard plots (from base R).
– Marek
Jul 25 '13 at 14:15
@Grego...
Is there a JavaScript MVC (micro-)framework? [closed]
...pproach enables you to select only the features you need. As of 2.0, it's based on jQuery.
On progressively enhancing your website, that's left up to the user as JMVC provides just a middle layer for development - it's up to you to make that design choice yourself.
However, JavaScriptMVC is sim...
Using Rails serialize to save hash to database
...pping ids to a number of attempts in my rails app. My migration to the database to accommodate this new column:
3 Answers
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