I stumbled upon B::Lint's magic-diamond documentation which states that <> (also known as <ARGV>) internally uses perl's two-argument open.

This means that if <> encounters a filename "rm * |  " (just has to end with pipe "|" and optional whitespace), then it executes the shell command 'rm *'. Example:

$ mkdir diamondtest
$ cd diamondtest
$ touch 'rm * | ' a b c d  # create 5 files
$ ls  # now you see it
$ perl -pe 1 *
$ ls  # now you don't -- no files
[download]

Shouldn't this be fixed with 3-argument open? I really like the magic-diamond for quick one-liners, but this just sounds all the security/robustness alarm bells.

Any recommended idioms to replace the following?

while (defined($_ = <ARGV>)) { ... }
[download]

Update: An idiom would be to use ARGV::readonly

Update 2: If you're like me and like to write lots of one-line filters like:

# strip blank lines
perl -pe 's=^\s*$=='
[download]

as an idiom, add the taint switch -T:

perl -Tpe 's=^\s*$=='
[download]

I don't fully agree with it, but it's the least we've got to curb the <ARGV> magic, besides ARGV::readonly, and not compromise the terseness of the one-liner.

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