Which is better on performance: double quoted strings with variables or single quoted strings with concatenations?

Question

I know that using single quotes around a string in PHP is faster than using the double quotes because PHP doesn\'t need to check for variable presence in the single quoted s

Answer 1

I wholeheartedly agree with Jonathan Sampson on this issue, but there's a solution which I believe is faster than the ones you posted. Using multiple arguments with echo:

echo 'foo bar', $baz;

This only applies when using the echo statement, in any other context concatenation is probably better, but I strive for readability in this so I use interpolation whenever possible.