F#度量单位，通用性问题2 [英] F# Units of measure, problems with genericity 2

问题描述

接着这个问题，我似乎还是与可能的前沿作斗争，尽管我不认为我在做任何特别前沿的事情:

Following on from this question, I still seem to be battling at the frontiers of what is possible, though I don't think that I'm doing anything particularly bleeding edge:

type Vector2d = { X: float<'u>; Y: float<'u> }

给我错误FS0039:未定义计量单位参数'u'.

还有

type Vector2d = { X: float<_>; Y: float<_> }

给我错误FS0191:此声明中不允许使用匿名计量单位变量.

函数可以处理通用"度量单位，但类型不能吗?

Is it the case that functions can handle 'generic' units of measure, but types can't?

推荐答案

type Vector2d<[<Measure>]'u> = { X: float<'u>; Y: float<'u> }

应该可以解决问题

注意:从1.9.6.2 CTP版本开始，这是正确的，但是此api当前不被视为稳定的

Note: This is correct as of the 1.9.6.2 CTP release but this api is not currently viewed as stable

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