positions(VisibleList,Function) -- which elements of a list satisfy a condition

positions(VisibleList,Function) -- which elements of a list satisfy a condition

Synopsis:

Function: positions -- which elements of a list satisfy a condition

Input:

an instance of class VisibleList.

an instance of class Function.

Code:

     -- ../../../Macaulay2/m2/structure.m2:8-10
     positions(VisibleList,Function) := (v,f) -> (
          apply(select(pack(2, mingle{v,0 .. #v-1}), p -> f p#0), p -> p#1)
          )