while-loop

<?php $i = 0; while(conditionals...) { if($i == 0) print "<p>Show this once</p>"; print "<p>display everytime</p>"; $i++; } ?> Would this only show "Show this once" the first time and only that time, and show the "display everytime" as long as the while loop goes thru? Yes, indeed. You can also combine the if and the increment, so you won't forget to increment: if (!$i++) echo "Show once."; Rather than incrementing it every time the loop runs and wasting useless resource, what you can do is, if the value is 0 for the first time, then print the statement and make the value of the variable as

This question already has an answer here : Which file is Perl's diamond operator (null file handle) currently reading from? (1 answer) A simple program with while( <> ) handles files given as arguments ( ./program 1.file 2.file 3.file ) and standard input of Unix systems. I think it concatenates them together in one file and work is line by line. The problem is, how do I know that I'm working with the first file? And then with the second one. For a simple example, I want to print the file's content in one line. while( <> ){ print "\n" if (it's the second file already); print $_; } The diamond

I found this piece of code on Wikipedia. #include <stdio.h> int main(void) { int c; while (c = getchar(), c != EOF && c != 'x') { switch (c) { case '\n': case '\r': printf ("Newline\n"); break; default: printf ("%c",c); } } return 0; } I'm curious about expression used as condition for while loop: while (c = getchar(), c != EOF && c != 'x') It's quite obvious what it does, but I've never seen this construction before. Is this specific to while loop? If not, how does parser/compiler determine which side of comma-separated expression returns boolean value for while loop? The comma operator is a