The code:

my @hash{@keyarray} = @valuearray;

Should be understood as:

my($hash{$keyarray[0]}, $hash{$keyarray[1]}, ...) = @valuearray;

Once this is understood, it should be easier to see why Perl considers the expression to be a syntax error. Perl does not know what my($hash{$key}); means. The exact error is `Can't declare hash slice in "my" at ...'

For an interesting comparison, consider the following similar-looking code:

local @hash{@keyarray} = @valuearray;

This code actually works, because local($hash{$key}); is perfectly valid and means 'override the value of $hash{$key} until this block completes'.

In reply to Re: Complicated Hash Construction. by MarkM
in thread Complicated Hash Construction. by coolmichael

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