‘when‘ expression must be exhaustive, add necessary ‘xxx‘, ‘null‘ branches or ‘else‘ branch instead

1.问题

Kotlin版本升级导致编译报错：'when' expression must be exhaustive, add necessary 'xxx', 'null' branches or 'else' branch instead

2.原因

Kotlin1.7之后when强制封闭问题，1.6及之前的版本只做Waring提示，1.7之后变成了Error导致无法编译通过，

3.解决

所以我们在写when时尽可能的加上else，或者穷举所有可能出现的情况。

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‘when‘ expression must be exhaustive, add necessary ‘xxx‘, ‘null‘ branches or ‘else‘ branch instead

1.问题

2.原因

3.解决

‘when‘ expression must be exhaustive, add necessary ‘xxx‘, ‘null‘ branches or ‘else‘ branch instead相关推荐

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