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Re: [vox-tech] Passing the reference to a hash - in perl
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Re: [vox-tech] Passing the reference to a hash - in perl



On Sun, Jul 01, 2001 at 01:15:52PM -0500, Jay Strauss wrote:
> Doooh, I knew that.  I stared at that thing for 30 min and didn't notice.  I
> don't really understand the mention of using strict and using references.
> Seems OK to me.

In perl there are `hard' and `symbolic' references. Hard refs are the normal
kind; the variable holding the ref contains opaque data.

Symbolic refs are really just strings. When you use a string in a context the
requires a reference, perl automagically supplies a hard reference to the
variable or function whose name (minus the prefix $, @, %, *, or &) is the
string found in the symbolic ref variable.

This can be useful sometimes, but is guaranteed to cause confusion a lot of
the time because it is terribly easy to mistakenly pass the variable holding
the data instead of a reference to it, leading to unexplained program failure
with no error message. The strict refs pragma disallows symbolic refs. I
happen to disagree with the previous poster: this is very much a good thing
if you do not indent to use sylbolic refs.

-- 
Henry House
OpenPGP key available from http://romana.hajhouse.org/hajhouse.asc

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