Print a list of one or more expressions, separated by commas.
(print-expr-list exprs pstate) → new-pstate
This is used to print argument expressions of function calls. That is, in fact, the only place of our abstract syntax that uses expr-list.
The case of an empty expression list is handled in print-expr. This function is called when there is at least one.
This is why we separate the expressions with commas.
Since the grammar rule for