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@JaviSoto
JaviSoto / gist:5906004
Last active June 27, 2023 10:25
Mark designated initializer at compile time
#define MSDesignatedInitializer(__SEL__) __attribute__((unavailable("Invoke the designated initializer `" # __SEL__ "` instead.")))
// Sample usage:
- (instancetype)initWithObject:(id)object;
- (instancetype)init MSDesignatedInitializer(initWithObject:); // <- This even gets auto-complete.
// Now calling init on this class would throw a warning.
@jboner
jboner / latency.txt
Last active May 6, 2024 07:06
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@jlong
jlong / uri.js
Created April 20, 2012 13:29
URI Parsing with Javascript
var parser = document.createElement('a');
parser.href = "http://example.com:3000/pathname/?search=test#hash";
parser.protocol; // => "http:"
parser.hostname; // => "example.com"
parser.port; // => "3000"
parser.pathname; // => "/pathname/"
parser.search; // => "?search=test"
parser.hash; // => "#hash"
parser.host; // => "example.com:3000"