I think any type of parsing benefits from some happy-path/unhappy-path support in the language, because parsing essentially is about figuring out whether your input conforms to some format and then translating it into a more useful representation. And it often works in a nested way, where you parse sub-parts of your input and then combine those parts later. If you don’t use some form of exceptions/result types/CPS, you end up with lots of code like
if first part of input_data has format a:
extract first part of output from input_data
You need the checks because otherwise your program will blow up in the extract step, which in parsing is often not what you want, as you might need to try a different way of parsing the same thing first. Internally, the check and the extraction often do pretty similar things, so you’re duplicating your work.
Here, exceptions for control flow can help, because instead of the check, you just try to extract, and if it doesn’t work, you try the next version. (However, result types usually work better for this, in programming languages that support them.)
And as the last point, in my experience, many programming problems are handled cleanest when treating them as the problem of parsing some form of input (not necessarily a string) into some form of output. So this comes up more often than one might first think.
[Also, Python uses exceptions for some types of control flow internally. For example, StopIteration is thrown by Iterators for the (rather unexceptional) case that the Iterator is finished producing output. Admittedly, you can almost always just use a for loop, except when you want access to the StopIteration’s value at the end.]
Here, exceptions for control flow can help, because instead of the check, you just try to extract, and if it doesn’t work, you try the next version. (However, result types usually work better for this, in programming languages that support them.)
And as the last point, in my experience, many programming problems are handled cleanest when treating them as the problem of parsing some form of input (not necessarily a string) into some form of output. So this comes up more often than one might first think.
[Also, Python uses exceptions for some types of control flow internally. For example, StopIteration is thrown by Iterators for the (rather unexceptional) case that the Iterator is finished producing output. Admittedly, you can almost always just use a for loop, except when you want access to the StopIteration’s value at the end.]