pattern match好像还是有bug

欢迎
1 
type picture enum {
    Gif
    Jpg
    Png
}

func create_pictures() -> array[picture] {
    let ary: array[picture] = array_make(10, picture::Gif)
    var i = 0
    while i < 10 {
        if i < 3 {
            ary.set(i, picture::Gif)
        } else if i >= 3 && i < 7 {
            ary.set(i, picture::Jpg)
        } else {
            ary.set(i, picture::Png)
        }
        i = i + 1
    }
    ary
}

let pictures: array[picture] = create_pictures()

func init {
    var i = 0
    while i < pictures.length() {
        let picture = pictures[i]
        match picture {
            Gif => "picture is Gif\n".output() 
        }
        i = i + 1
    }
}


====== Compilation Statistics ======
Wasm size: 851B
Time cost: 5ms
---
picture is Gif
picture is Gif
picture is Gif
RuntimeError: unreachable

---
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2

目前我们的 pattern match 还没有上类型检查，实际你没有指定 Jpg 和 Png 这两种 case 下应当如何处理。默认我们会当做这两种case不会遇到，如果被执行到就会抛出 unreachable 异常。如果这不是你想要的，你可以改成这样：


        match picture {
            Gif => "picture is Gif\n".output() 
        |   Jpg => ()
        |   Png => ()
        }
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