This assertion is patently false. Parens make it quite trivial to parse and render the underlying tree structuee rather obvious. Concatenating programs is just a matter of splicing a subtree into the target tree.
Here's a proof.
- In S-Expressions with parens, there are infinite ways to write any given abstract syntax tree.
- In Tree Notation, there is only 1 way to write any given abstract syntax tree.
If you change one letter, you get a different tree.
- Say I wrote programs in a Tree Language with a root node called "dumpToConsole" and I want to
rename all such nodes to "print". I can write a type-safe ad hoc parser that does
a simple search replace "/\ndumpToConsole/print/",
using Tree Notation. If it were in S-Expressions, I'd have to use a full parser.