in reply to Re: Search a hash for STDIN and report findings
in thread Search a hash for STDIN and report findings

Definitely better. I have put the entire little script below. The user name is formatted and stored in a hash key with the password as the value. I want to then have the user put in a first or last name and have it searched against the hash and return the user name and pass word if it is found..problem I am having is case sensitivity. Please pardon my useless script, I am trying to learn Perl. 

while(1)
{
        print "Please enter your first name\n";
        chomp ($fname =<STDIN>);
           {
                last;
           }
        print "Please enter your last name\n";
        chomp ($lname =<STDIN>);
           {
                last;
           }
        print "Please enter a password\n";
        chomp ($password =<STDIN>);
           {
                last;
           }
        print "Please enter 'done' or hit your return key\n";
        chomp ($ending =<STDIN>);
        if ($ending eq '\n' or 'done')
           {
                last;
           }
}

my $username = "$lname, $fname";
%new_hash;
$new_hash{$username} = $password;

print "To search for a user please type in the last name, firstname an
+d hit enter.\n";

while(<STDIN>) {
    chomp;
    if (exists $new_hash{$_}){
        print "The username is $username and the password is $password
+, please enter another name to search for.\n";
    } else {
        print "I'm sorry, there is no one here by that name please try
+ again.\n";
        }
}

[download]
Thank you! TW

Replies are listed 'Best First'.
Re^3: Search a hash for STDIN and report findings
by moritz (Cardinal) on Feb 07, 2008 at 19:37 UTC
    One problem is that your hash is empty after you tried to enter the values - there is no assignment to the hash.

    If you want to know the values of your hash, here's a little trick: 

    use Data::Dumper;
my %passwords; # please don't name your data structure
               # %new_hash. That's not a telling name at 
               # all
while(1)
{
        print "Please enter your first name\n";
        chomp ($fname =<STDIN>);
           {
                last;
           }
        print "Please enter your last name\n";
        chomp ($lname =<STDIN>);
           {
                last;
           }
        print "Please enter a password\n";
        chomp ($password =<STDIN>);
           {
                last;
           }
        print "Please enter 'done' or hit your return key\n";
        chomp ($ending =<STDIN>);
        if ($ending eq '\n' or 'done')
           {
                last;
           }
}

my $username = "$lname, $fname";

# here comes the magic:
print Dumper \%passwords; # you'll see that the hash 
                          # is empty.

# rest of the script goes here

    [download]

    You have to actually store the passwords: 

    while(1)
{
        print "Please enter your first name\n";
        chomp ($fname =<STDIN>);
           {
                last;
           }
        print "Please enter your last name\n";
        chomp ($lname =<STDIN>);
           {
                last;
           }
        print "Please enter a password\n";
        chomp ($password =<STDIN>);
           {
                last;
           }
        # important: store the passwords in %passwords
        $passwords{$fname} = $password;

        print "Please enter 'done' or hit your return key\n";
        chomp ($ending =<STDIN>);
        if ($ending eq '\n' or 'done')
           {
                last;
           }
}

    [download]

    Additionally the usual tips apply: always use strict; use warnings and declare your variables.

    To answer your original question: to achieve case insensitivity, use lc or uc to convert the strings (for example first name) to all lower or all upper case, and only then store them.

[reply]
[d/l]
[select]
      you guys probably want 
      if ($ending eq '\n' or 'done')

      [download]

      to be 

      if ( ($ending eq '\n') or ($ending eq 'done') )

      [download]
[reply]
[d/l]
[select]
        We're both idiots, toolic ;-) (no offense meant).

        '\n' would only be the case if the user entered a literal backslash followed by an n. Not very likely to be intended. Since $ending is already chomped there's no need for a newline check at all.

        if ($ending eq 'done') is just fine, I think.

[reply]
[d/l]
[select]
      Thank you for your infinite patiences
[reply]

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