How to match parentheses / brackets in pyparsing

Question

I have a grammar token specified as:

list_value = Suppress(oneOf("[ (")) + Group(
    delimitedList(string_value | int_value))("list") + Suppress(oneOf("] )"))

However, this obviously allows (foo, bar]

How do I enforce that the lists opening and closing characters must match?

Answer 1

You make a list a choice between two rules: one for parentheses and one for square brackets. Thanks for bringing up pyparsing. I like it. My answer for your question is:

delim_value = Group(delimitedList(string_value | int_value))("list")
list_value = Or( (Suppress("[") + delim_value + Suppress("]"),
                  Suppress("(") + delim_value + Suppress(")")) )