A Cross-Platform String Library Written in Swift | Hacker News Reader

A Cross-Platform String Library Written in Swift

github.com

32 pointsfebin12 comments

Two things I'm not a fan of so far in the API design.

1) Function names are misleading or not descriptive enough. E.g. isAlpha(). I assumed this meant is alphanumeric, but it actually means isAlphabetic (as in no numeric values at all). isAlphanumeric() clears this up, but just call the first isAlphabetic and remove any ambiguity. 2) Explicit binary inverts; e.g. isUppercased(), isLowercased(). This leads to bad coding style as conditionals that point in the affirmative usually leads to easier to read code. If it's not uppercased of course its lowercased, so why keep a function around to point this out? Save on the cognitive load on the users and just keep one around. Let them negate it for the desired result.

Otherwise, thank you for contributing what looks to be a pretty handy library that isn't tied to just MacOS/iOS and Xcode. I'm really starting to enjoy Swift and am curious to use it in non-client environments soon and a library like this is a pretty nice tool to have.

> 1) Function names are misleading or not descriptive enough. E.g. isAlpha(). I assumed this meant is alphanumeric, but it actually means isAlphabetic

Why should it mean alphanumeric? C's isalpha() also tests for being a letter, for instance, and has isalnum() for alphanumericness.

> If it's not uppercased of course its lowercased

If you're working exclusively with ASCII and ignoring non-letter characters, yes. But is this library bound by those constraints?

what non-letter character should succeed in both isLowercase and isUppercase?

None. But letters can be neither lowercase nor uppercase.

In which case, the function(s) should really be throwing some kind of error, since they can't reasonably be applied to the input.

But checking !(isUppercase(str) || isLowercase(str)) to see if its not case-able(?) is absurd

Obviously you'd instead want the function notCaseable(str).

Why is @discardableResult used here?

https://github.com/ArtSabintsev/Guitar/blob/0dc71e9dea5ba975...

Strings are one of the most difficult things to get right in any standard library. You can be like C and offer barebones support, but many developers will make mistakes. You can be like Java and offer much more complete support, but you can never quite satisfy everyone's use case and people complain. I personally would never have even thought to include functions like `kebabCased`, this is a very interesting take on a string library. Overall, good stuff.

How on Earth is this 'cross-platform'?

Or a string library?

It is a library of functions that manipulate objects of the language built-in String type, not a library that implements a string type from scratch.

That's still a string library. string.h doesn't implement any "string type" from scratch either.

How is it not?

It doesn't rely on any Apple-specific APIs.

Swift is cross-platform (and open source), and obviously this doesn't depend on parts of Swift (like the iOS/OS X only APIs) that are not available on other platforms, but only on the core (and portable) libs.

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