TreeInsert

TreeInsert[tree, child, pos] inserts child at the position specified by pos in tree.

• TreeInsert[tree, child, {pos1, pos2, ...}] inserts child at several positions.
• TreeInsert[child, pos] represents an operator form of TreeInsert that can be applied to a tree.

Examples

Insert a new child into a tree:

tree = Tree[a, {Tree[b, {}], Tree[c, {}]}];
TreeInsert[tree, Tree[d, {}], {1}]

Insert at multiple positions:

TreeInsert[tree, Tree[x, {}], {{1}, {2}}]

Using the operator form:

TreeInsert[Tree[new, {}], {2}][tree]

Please visit the official Wolfram Language Reference for more details.