Look at the following snippet. 

perl -e 'open strict, ">&", STDOUT or die; use strict; print strict fo
+obar, "\n";'

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This prints foobar so clearly foobar is interpretted as a bareword. However, we use strict, so that should disallow barewords. Why is this? (The title of the post can give a hint.)

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Re: A feature of use
by ambrus (Abbot) on Aug 20, 2008 at 19:57 UTC

    In fact, even this works. 

    perl -e 'if (0) { open strict; } use strict; print STDOUT foobar, "\n"
+;'

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Re: A feature of use
by jdalbec (Deacon) on Aug 20, 2008 at 22:45 UTC
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      It certainly seems so, we can even verify this like this. 

      perl -we 'use IO::Handle; { package IO::Handle; sub import { warn "imp
+ort called on handle $_[0]"; } } if (0) { open strict; } BEGIN { warn
+ "about to use strict"; } use strict; BEGIN { warn "after use strict"
+; } use warnings;'

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      However, I don't understand why this happens even before the open is called at all. I originally wrote the snippet with open in a BEGIN, because I thought that was the only way to trigger this. In fact, as open $foo, ... should autovivify a new glob with filehandle each time it's executed, I don't really know why open strict should do anything in compile time.

      Indeed, notice how my $h = *strict; open $h; triggers the feature if it's ran in a BEGIN block before use strict;, but not if it's just compiled before it.

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Re: A feature of use
by ambrus (Abbot) on Jul 18, 2016 at 09:34 UTC
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