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Class constructors in signatures?
f#

This seems like it should be so simple that I could have easily found it elsewhere, but even looking through the spec I couldn't figure out a solution.

In my .fs file I have,

type Foo(bar: int) =

member this.Baz() = bar

if I write in my .fsi

type Foo(bar: int) =

member Baz: unit -> int

I get a parse error with the left paren. Now if I write,

type Foo =

member Baz: unit -> int

it is happy, except that clients have no way of creating a Foo. Is it really the case that the only way to deal with this is to create a helper function to allocate a Foo?

.

Here's a sample

fsi:

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namespace Blah
type Foo = class
    new : int -> Foo
    member Baz : unit -> int
end

fs:

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namespace Blah
type Foo(bar: int) = 
    member this.Baz() = bar

Note that an effective way to discover the syntax for signatures is to run e.g.

fsc --sig:Out.fsi SomeFile.fs

and then inspect Out.fsi.

By on 9/7/2009 2:41 AM ()

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