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@leonid-shevtsov
leonid-shevtsov / gist:2550423
Created April 29, 2012 13:22
Like find(:first), but asserts that query returns exactly one element. Works with scopes.
class MyModel < ActiveRecord::Base
def self.one(find_hash={})
results = find(:all, find_hash)
if results.size != 1
raise "Expected one record, found #{results.size}"
else
return results[0]
end
end
end
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

@quchen
quchen / trolling_haskell
Last active October 10, 2025 04:32
Trolling #haskell
13:15 <xQuasar> | HASKELL IS FOR FUCKIN FAGGOTS. YOU'RE ALL A BUNCH OF
| FUCKIN PUSSIES
13:15 <xQuasar> | JAVASCRIPT FOR LIFE FAGS
13:16 <luite> | hello
13:16 <ChongLi> | somebody has a mental illness!
13:16 <merijn> | Wow...I suddenly see the error of my ways and feel
| compelled to write Node.js!
13:16 <genisage> | hi
13:16 <luite> | you might be pleased to learn that you can compile
| haskell to javascript now
@gmccreight
gmccreight / master.vim
Last active November 21, 2024 14:36
A script that gives you a playground for mastering vim
" copy all this into a vim buffer, save it, then...
" source the file by typing :so %
" Now the vim buffer acts like a specialized application for mastering vim
" There are two queues, Study and Known. Depending how confident you feel
" about the item you are currently learning, you can move it down several
" positions, all the way to the end of the Study queue, or to the Known
" queue.
" type ,, (that's comma comma)