Mathematica's unified symbolic architecture allows immediate generalization of part-oriented list operations to arbitrary expressions—supporting operations both on individual parts, and on collections of parts at specified levels in expression trees.
Part (
..[[..]]) get any part of an expression (reset with
=)
ReplacePart — replace numbered parts of an expression
Position — find the positions of any pattern in an expression
Cases — find cases of any pattern in an expression
MapAt — apply a function at particular positions in an expression
Map (
/@) — apply a function at specified levels in an expression
MapAll (
//@) — apply a function to all parts of an expression
Heads — option for specifying whether to include heads
Sow,
Reap — collect parts "sown" inside of an expression
