Now, can any monk more wise or at least more educated than I, explain why?

I was trying to make a little wrapper routine for calls to Win32::OLE methods to combine them with error checks, so I don't have to rewrite the error checking code for each call.

Here is a baby example using my first attempt at OLECheck: 

#!c:/sw/perl/bin/perl.exe

use warnings;
use strict;
use Win32::OLE;

our $project;

sub OLECheck (&$) {
    my ($sub,$msg) = @_;
    my $result = eval &$sub;
    die "Couldn't $msg: $@" if $@;
    my $error = Win32::OLE->LastError();
    die "Couldn't $msg: $error" if $error;
    $result;
}

OLECheck {$project = Win32::OLE->new("ISWiAutomation9.ISWiProject");}
         "instantiate the Developer Automation Interface";

print "success!\n";

[download]
Instead of "success!" I got: 
Couldn't instantiate the Developer Automation Interface: Can't modify 
+constant item in scalar assignment at (eval 2) line 2, at EOF
Bareword "Win32::OLE" not allowed while "strict subs" in use at (eval 
+2) line 1.

[download]
Changing the eval line like so: 
my $result = eval {$sub->()};

[download]
fixes the problem.

Even though my immediate problem is solved, I'm still curious as to why the original failed in the way that it did.

--DrWhy

"If God had meant for us to think for ourselves he would have given us brains. Oh, wait..."

Retitled by Steve_p from 'I solved my problem!'.

In reply to I solved my Problem! (Confusion with eval) by DrWhy

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