> it's quite pointless to expect one library to handle all of it Libraries don't just come with implementation, but also a use model. Perl, for example has: S

> it's quite pointless to expect one library to handle all of it Libraries don't just come with implementation, but also a use model. Perl, for example has: Spreadsheet::XLSX Spreadsheet::ParseExcel These have very different user (programmer) interfaces -- so different that now there's a Spreadsheet::ParseXLSX which just allows programmers (and programs) used to one interface, consume the new files with very little changes. This rust library has it's own model, and if it's a good model it makes sense to implement other file formats with this model -- and indeed this is a good way to test if it's a good model. Other things like CSV are so fundamentally different from XLS/XLSX that they're going to have a different model, and so it makes sense that these require different libraries.