NodeVisitor class for PEG parser in Python

Question

Imagine the following types of strings:

if ((a1 and b) or (a2 and c)) or (c and d) or (e and f)

Now, I\'d like to get the expressions in pa

Answer 1

If you only want to return each outermost factor, return early and do not descend into its children.

def walk(node, level = 0):
    if node.expr.name == "factor":
        print(level * "-", node.text)
        return
    for child in node.children:
        walk(child, level + 1)

Output:

----- ((a1 and b) or (a2 and c))
----- (c and d)
------ (e and f)