print is not a function

This comes from a seemingly weird question:

if (print("1\n") && print("2\n") && print("3\n") && print("4\n")) {
    ;
}

What do you expect this code to output?

Actually The output is:

4
111

Many times we ignore that print is a grammatical structure (language constructs), it is not a function, and the list of parameters does not require parentheses (even if you write Parentheses, parentheses will also be ignored during the syntax analysis stage), it is just an "expression (expr)" that always returns 1:

expr :
   T_PRINT expr
 | '(' expr ')'
;
所以其实上面的代码在php看来是:
if (print ("1\n" && print ("2\n" && print ("3\n" && print "4\n")))) {
  ;
}

So, output 4, and then output "3\n" The result of && print is 1, then "2\n" && 1 is output, and finally "1\n" && 1

And if we want to achieve the intended intention of the above code, we should Write this:

if ((print "1\n") && (print "2\n") && (print "3\n") && (print "4\n")) {
    ;
}

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