Performance: " or ' PHP [duplicate]

Question

I'm working on a big project in php and I need to make sure it's all fast. So I'm wondering: what is faster to use, " or ' ? (Eg: $_SESSION['example'] or $_SESSION["example"])

Answer 1

You shouldn't even care about this. It makes no real difference. No practical impact.

http://nikic.github.io/2012/01/09/Disproving-the-Single-Quotes-Performance-Myth.html

https://speakerdeck.com/dshafik/phpaustralia-2015-php-under-the-hood

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Lets use the same benchmark data from the post by Mark Smit:

For a real speed benchmarks between quotes you can look at http://www.phpbench.com/

Q: Is a there a difference in using double (") and single (') quotes for strings. Call 1'000x

A: In today's versions of PHP it looks like this argument has been satisfied on both sides of the line. Lets all join together in harmony in this one!