问题
FooBarBaz -> foo-bar-baz
解答
type KebabCase<S, T extends string = ""> =
S extends `${infer First}${infer Rest}`
? First extends Uncapitalize<First>
? KebabCase<Rest, `${T}${First}`>
: T extends ""
? KebabCase<Rest, `${Uncapitalize<First>}`>
: KebabCase<Rest, `${T}-${Uncapitalize<First>}`>
: T;
拆分
- 利用大写转换之后变成小写和原来的对比
- 如果和原来一样就直接拼接
- 如果和原来不一样就判断是否是首字
- 根据判断结果添加
-
执行步骤
foo-bar
| S | T | First | Rest | First=U<First> | T="" | result |
|---|---|---|---|---|---|---|
| foo-bar | f | oo-bar | true | never | KebabCase<oo-bar, f> | |
| oo-bar | f | o | o-bar | true | never | KebabCase<o-bar, fo> |
| o-bar | fo | o | -bar | true | never | KebabCase<-bar, foo> |
| -bar | foo | - | bar | true | never | KebabCase<bar, foo-> |
| bar | foo- | b | ar | true | never | KebabCase<ar, foo-b> |
| ar | foo-b | a | r | true | never | KebabCase<r, foo-ba> |
| r | foo-ba | never | never | never | never | r |
FooBarBaz
| S | T | First | Rest | First=U<First> | T="" | result |
|---|---|---|---|---|---|---|
| FooBar | F | ooBar | false | true | KebabCase<ooBar, f> | |
| ooBar | f | o | oBar | true | never | KebabCase<oBar, fo> |
| oBar | fo | o | Bar | true | never | KebabCase<Bar, foo> |
| Bar | foo | B | ar | false | never | KebabCase<ar, foo-b> |
| ar | foo-b | a | r | true | never | KebabCase<r, foo-ba> |
| r | foo-ba | r | true | never | KebabCase<never, foo-bar> | |
| never | foo-bar | never | never | never | never | foo-bar |