Difference between period and comma when concatenating with echo versus return?
I just found that this will work:
echo $value , " contiue";
but this does not:
return $value , " contiue";
While "." Works in both.
What is the difference between a period and a comma here?
return does only allow one single expression. But echo allows a list of expressions where each expression is separated by a comma. But note that since echo is not a function but a special language construct, wrapping the expression list in parenthesis is illegal.
the . is the concatenation operator in PHP, for putting two strings together. The comma can be used for multiple inputs to echo.
You also have to note that echo as a construct is faster with commas than it is with dots.
So if you join a character 4 million times this is what you get:
echo $str1, $str2, $str3;
About 2.08 seconds
echo $str1 . $str2 . $str3;
About 3.48 seconds
This is because PHP with dots joins the string first and then outputs them, while with commas just prints them out one after the other.
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