in reply to Why does this code think I'm trying to use symbolic references?

print $n ... expects $n to contain a file handle. 1000 is not a file handle and "strict refs" forbids using the string to reference a variable. Consider:

#! perl

my $n = 'STDOUT';

print $n "Now we's happy\n";

use strict;
print $n "Now we's not\n";

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Prints:

Now we's happy
Can't use string ("STDOUT") as a symbol ref while "strict refs" in use
+ at ...\noname.pl line 8.

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Premature optimization is the root of all job security

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Re^2: Why does this code think I'm trying to use symbolic references?
by BrowserUk (Patriarch) on Jun 12, 2016 at 22:25 UTC
    print $n ... expects $n to contain a file handle.

    But print $n + 4; doesn't; and that was my intent. And in (almost, if not) all other circumstances $n +4 and $n + 4 are equivalent, so It just didn't click even after I found that adding another space fixed the problem.

    As I'm normally quite prodigious with my horizontal whitespace, it's just not something I've encountered before.

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      ... I'm normally quite prodigious with my horizontal whitespace ...

      Either prodigality or parsimony seem to work; e.g.,  print $n+4; also avoids the problem. Apparently it's only  $n +4 that Perl looks at and says "Oh, of course: a unary plus!" (I haven't tested it, but I assume the same would happen | I've tested it, and the same thing happens with a pseudo-unary minus.)

      Update: Per perlop, unary + and - have higher precedence than the binary operators.

      Give a man a fish:  <%-{-{-{-<

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