我正在做一個國際象棋游戲，我想在同一個陳述句中執行一系列型別斷言var，然后將它們傳遞給處理它的函式，但顯然，Go 不允許我分配給常規變數和切片同一陳述句中的索引：
// inside a function:
asserts := make([]bool, 0, 10)
assertionHandler := func(ok *[]bool) {
for _, b := range *ok {
if !b {
msg := "pieceCliked: failed while trying to do type assertion\n%s\n\n"
utils.LogPrintError(errors.New(fmt.Sprintf(msg, string(debug.Stack()))))
}
}
*ok = make([]bool, 0, 10)
}
var (
possibleSquares []string
// The following results in a syntax error: expected type, found '='
dataObject, asserts[0] = data.(map[string]any)
playerData, asserts[1] = dataObject["playerData"].(map[string]any)
square, asserts[2] = playerData["selectedPieceLocation"].(string)
piece, asserts[3] = playerData["selectedPiece"].(string)
color, asserts[4] = playerData["selectedPieceColor"].(string)
)
assertionHandler(asserts)
有可能做我想做的事嗎？
uj5u.com熱心網友回復：
不是你這樣做的方式，不。一個var塊定義了新變數及其型別，但您試圖將其分配給沒有型別的新變數（因此錯誤expected type）和該塊中現有切片的元素。
你可以這樣做：
var (
possibleSquares []string
dataObject map[string]any
playerData map[string]any
square string
piece string
color string
)
dataObject, asserts[0] = data.(map[string]any)
playerData, asserts[1] = dataObject["playerData"].(map[string]any)
square, asserts[2] = playerData["selectedPieceLocation"].(string)
piece, asserts[3] = playerData["selectedPiece"].(string)
color, asserts[4] = playerData["selectedPieceColor"].(string)
uj5u.com熱心網友回復：
另一個答案描述了為什么問題中的代碼不起作用。這是另一種解決方法：
撰寫斷言處理程式以使用可變引數：
func assertionHandler(asserts ...bool) bool {
result := true
for _, b := range assserts {
if !b {
result = false
msg := "pieceCliked: failed while trying to do type assertion\n%s\n\n"
utils.LogPrintError(errors.New(fmt.Sprintf(msg, string(debug.Stack()))))
}
}
return result
}
使用簡短的變數宣告來收集值和布爾結果：
dataObject, assert0 := data.(map[string]any)
playerData, assert1 := dataObject["playerData"].(map[string]any)
square, assert2 := playerData["selectedPieceLocation"].(string)
piece, assert3 := playerData["selectedPiece"].(string)
color, assert4 := playerData["selectedPieceColor"].(string)
if !assertionHandler(assert0, assert1, assert2, assert3, assert4) {
return
}
轉載請註明出處，本文鏈接：https://www.uj5u.com/yidong/511303.html
標籤：去变量