Re: Printing two variables in the same line

First, use strict; and use warnings.

Next, there's no need to use @grades to initialize %grades. Just my %grades = qw( ... ) will work fine.

As for why it's not printing you've committed the classic mistake of using the assignment operator when you meant to test for equality. perldoc perlop and look for eq.

Update: And you also don't need to explicitly use the concatenation operator. Just "$_ has a $student\n".

Update: And really you don't need $student at all. Just exists $grades{ $_ } and print "$_ has a $grades{ $_ }\n" without it.

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Re^2: Printing two variables in the same line by radiantmatrix (Parson) on Oct 07, 2004 at 20:50 UTC
Let me elaborate: `if ($student = "") {print "Cannot find that student, try again\n";}` [download] Says, essentially, if the result of assigning the value "" to $student is true.... The problem with that? `$student = ""` both returns a false value AND makes `$student` contain an empty string! The comparison operators are `==` for binary values (numbers, mostly) and `eq` for strings. What you really want is: `if ($student eq "") {print "Cannot find that student, try again\n";} ## OR, Better unless ($student) {print "Cannot find that student, try again\n";}` [download] That way, `$student` will still hold the value you expect when you reach your `print` statement. If you use the latter version, it will also function properly if `$student` is undefined for some reason ("" and undefined are slightly different, but both false). It's a very common mistake, and hard to catch. The above advice to `use strict;` and `use warnings;` is sound. Also, learning to use the perl debugger might have helped you here. radiantmatrix `require General::Disclaimer;`	[reply] [d/l] [select]
Re^3: Printing two variables in the same line by JustLikeThat (Initiate) on Oct 07, 2004 at 22:00 UTC
Thank you for taking the time to elaborate and the examples you gave. It was a great help!!!	[reply]
Re^2: Printing two variables in the same line by JustLikeThat (Initiate) on Oct 07, 2004 at 22:04 UTC
Thanks for the help. I'll learn more about the debugger soon.	[reply]