TreeReplacePart

TreeReplacePart[tree,pos->new] gives a tree in which the subtree of tree at the position specified by pos is replaced with new.

TreeReplacePart[tree,{pos1->new1,pos2->new2,…}] replaces subtrees at positions specified by posi with newi.

TreeReplacePart[tree,{pos1,pos2,…}->new] replaces all subtrees at positions specified by posi with new.

TreeReplacePart[tree,{{pos1,1,pos1,2,…}->new1,…}] replaces subtrees at positions specified by {posi,1,posi,2,…} with newi.

TreeReplacePart[pos->new] represents an operator form of TreeReplacePart that can be applied to a tree.

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