Responding to what you said before: I also believe that representing everything as a tree (why are programmers so obsessed with trees!?) is ridiculous: code is, quite simply, code. Outline structure or not, what matters is the actual meaning of the code, and this is part of your mental model of the program, not the syntax.

Compilers represent your code as a tree - a parse tree first, then an abstract syntax tree. That is how code is understood. It's not an arbitrary decision on raganwald's part.