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Heads

Heads
is an option for functions which use level specifications that specifies whether heads of expressions should be included.
  • Heads->True treats heads just like other elements of expressions for the purpose of levels.
  • Heads->False never includes heads as part of any level of an expression.
  • Most functions which use level specifications have the default setting Heads->False. One exception is Position, for which the default is Heads->True.
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