Interesting replies - including aspects that I had not even considered.

I think that one lesson (for me, at least) is that I should not have expected "-MPDL" to be as innocuous as I had assumed.
For that level of innocuity, I think I should instead have used "-mPDL".

But I'm still a bit confused about perl's handling of "some_func" when both "main::some_func" and "CORE::some_func" exist.
In the one-liner I gave (that loads PDL), both "main::srand" and "CORE::srand" exist - and perl decides that "srand(3)" means "main::srand(3)".
But in this next one-liner (where both "main::sqrt" and "CORE::sqrt" exist) perl goes the other way - and decides that "sqrt(2)" means "CORE::sqrt(2)". 
D:\>perl -wle "print sqrt(2);print main::sqrt(2); print CORE::sqrt(2);
+sub sqrt { return sprintf('%.6g', $_[0] ** 0.5) }"
1.4142135623731
1.41421
1.4142135623731

[download]
Why the inconsistency ?
And why no warnings about the ambiguity of calling "some_func()" when both "main::some_func()" and "CORE::some_func()" exist ?

Cheers,
Rob

In reply to Re: PDL and srand puzzle by syphilis
in thread PDL and srand puzzle by syphilis

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