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For Loop

i have several variables (e.g file1, file2, file3 and so on)
how do i use a FOR LOOP that loops 10 times and each time it goes into the LOOP, the variable changes from file1 to file2 to file3 and so on?
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irene79
Asked:
irene79
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1 Solution
 
Kim RyanIT ConsultantCommented:
If you just want to access the variable contents:

@files = ($file1,$file2,$file3);
# get each element from array in sequence
foreach $file_n (@files) {
    $x = $file_n;
    # do something with $x
}

If you want to change the values of $file1 etc you will need to use variable references.
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ozoCommented:
# If you want to change the values of $file1 etc, you can just change $file_n in
foreach $file_n ($file1,$file2,$file3){
  # do something with $file_n
}
#if you just want the litteral strings file1, file2, file3 and so on, you could use
foreach $x ( "file1".."file9" ){
    # do something with $x
}
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irene79Author Commented:
sorry i got the answer already.
but can i ask ..
if i have a if else statement inside a for loop .. how do i break inside a if statement and cont on to the for loop?

and can i noe the syntax for "die"?
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ozoCommented:
What do you want to do with an if else statement inside a for loop ?
Do you want the last, or next statement?

perldoc -f die
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irene79Author Commented:
for eg.

for($var1=1;$var1 <10; $var1++){
  if ($var1 == 4)
  {
     get out from here and continue with counter 5-10. acts something like a BREAK to go to the next counter.
  }
}

i can use perldoc -f die in anywhere i wanna quit the program?

u gave me this code b4 .. is there any difference? die $@||"invalid date"

i'll increase the points for u .. thanx for ur help ozo :)
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ozoCommented:
for $var1 ( 1..9 ){
  next if $var1 == 4;
 
}



`perldoc -f die`
    die LIST
            Outside an `eval()', prints the value of LIST to
            `STDERR' and exits with the current value of `$!'
            (errno). If `$!' is `0', exits with the value of `($? >>
            8)' (backtick `command` status). If `($? >> 8)' is `0',
            exits with `255'. Inside an `eval(),' the error message
            is stuffed into `$@' and the `eval()' is terminated with
            the undefined value. This makes `die()' the way to raise
            an exception.

            Equivalent examples:

                die "Can't cd to spool: $!\n" unless chdir '/usr/spool/news';
                chdir '/usr/spool/news' or die "Can't cd to spool: $!\n"

            If the value of EXPR does not end in a newline, the
            current script line number and input line number (if
            any) are also printed, and a newline is supplied. Hint:
            sometimes appending `", stopped"' to your message will
            cause it to make better sense when the string `"at foo
            line 123"' is appended. Suppose you are running script
            "canasta".

                die "/etc/games is no good";
                die "/etc/games is no good, stopped";

            produce, respectively

                /etc/games is no good at canasta line 123.
                /etc/games is no good, stopped at canasta line 123.

            See also `exit()' and `warn()'.

            If LIST is empty and `$@' already contains a value
            (typically from a previous eval) that value is reused
            after appending `"\t...propagated"'. This is useful for
            propagating exceptions:

                eval { ... };
                die unless $@ =~ /Expected exception/;

            If `$@' is empty then the string `"Died"' is used.

            You can arrange for a callback to be run just before the
            `die()' does its deed, by setting the `$SIG{__DIE__}'
            hook. The associated handler will be called with the
            error text and can change the error message, if it sees
            fit, by calling `die()' again. See the section on
            "$SIG{expr}" in the perlvar manpage for details on
            setting `%SIG' entries, and the section on "eval BLOCK"
            for some examples.

            Note that the `$SIG{__DIE__}' hook is called even inside
            eval()ed blocks/strings. If one wants the hook to do
            nothing in such situations, put

                    die @_ if $^S;

            as the first line of the handler (see the section on
            "$^S" in the perlvar manpage).

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irene79Author Commented:
thanx ozo
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