Punctuation would be part of orthography which is usually considered distinct.
Consider you can have multiple writing systems for a single language, that single language would have a single set of grammar rules, but would have multiple orthographic rules applied to it.
Put another way, if I was to invent apostropheless English which was exactly like English but just omits all written apostrophes that wouldn't change the rules of English grammar, possessives would still be possessive etc.
Consider you can have multiple writing systems for a single language, that single language would have a single set of grammar rules, but would have multiple orthographic rules applied to it.
Put another way, if I was to invent apostropheless English which was exactly like English but just omits all written apostrophes that wouldn't change the rules of English grammar, possessives would still be possessive etc.