While this use of undef works in all perl 5 versions I am aware of, it is in fact not documented. I prefer 
@invslice[ @slice_idx ] = ();

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A math joke: r = | |csc(θ)|+|sec(θ)| |-| |csc(θ)|-|sec(θ)| |

In reply to Re^2: Inverse slices by ysth
in thread Inverse slices by Anonymous Monk

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