If you are compiling and running the project, you need to add a reference to the PowerPack using the 'add reference' dialog.
If you are sending this to the interactive window, you need to tell the interactive window to add the reference by using
#r "FSharp.PowerPack.dll";;
Yeah, I added the PowerPack reference in VS. LazyList even shows up in object browser...
I put your code into my usual Scratch VS solution and got the same error. Then I set the Specific Version property of the FSharp.PowerPack.dll reference to "False", rebuilt and the error disappeared.
F# often flags bogus errors in VS and they disappear when you manually rebuild.
If the solution predates the current F# then you might also consider creating a new one and copying the source across.
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Hi all,
I have a F# library with one fs file in it that refernces the Power Pack. The ENTIRE contents of that file is
#light
open Microsoft.FSharp.Collections
let lazyList =
LazyList.unfold
(fun x ->
if x < 13 then
Some(x, x + 1)
else
None)
When I try to run that I get:
File1.fs(6,5): error FS0039: The namespace or module 'LazyList' is not defined. A construct with this name was found in FSharp.PowerPack.dll, which contains some modules and types that were implicitly referenced in some previous versions of F#. You may need to add an explicit reference to this DLL in order to compile this code.
I've also tried adding "open Microsoft.FSharp.Collections.LazyList" which did not help either.
Thanks!