在Haskell中定义新类型
我是Haskell的新手，我想知道是否可以定义由其他类型列表定义的新类型。例如，我认为一个字符串定义为字符列表，因此我可以将向量定义为力值列表（在这种情况下为浮点值）吗？
如果是这样，我该如何声明和使用？
data vector = vector [float]
这足以定义新类型和构造函数？我可以打电话吗 x = vector [2.4,2.5,2.7]？
我正在使用GHCI，如果有什么不同
I am pretty new to Haskell, and I was wondering if one can define new types that are defined by lists of other types. For example, I assume a string is defined as a list of characters, so can I define a vector as a list of force values (in this case floating point values)?
If so, how can I declare and use this?
data Vector = Vector [Float]
Is this enough to define the new type and the constructor for it? Can I simply callx = Vector [2.4,2.5,2.7] for example?
I'm using ghci, if that makes any difference
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data typeName = typeconstructor type1 type2 ... typen只是创建函数typeconstructor :: type1-＆gt; type2-＆gt; ... - ＆GT;键入 - ＆gt; typeName，列表有特殊的句法糖，因此通常必须是list floatbe[float]之类的东西。因此，
data vector = vector [float]创建函数vector :: [float] - ＆gt;向量（请注意，功能和结果类型是共享名称的不同事物）。vector函数称为类型构造函数，类型构造函数是唯一可以以其名称具有初始大写字母的函数。Yes -
data TypeName = TypeConstructor Type1 Type2 ... TypeNjust creates a functionTypeConstructor :: Type1 -> Type2 -> ... -> TypeN -> TypeName, and there is special syntactic sugar for lists so that what would normally have to be something likeList Floatto instead be[Float].So
data Vector = Vector [Float]creates a functionVector :: [Float] -> Vector(note that the function and the result type are different things that happen to share a name).The
Vectorfunction is called a type constructor, and type constructors are the only functions that can have initial capital letters in their name.