NuGet Pack (#15)

README.md

@@ -1,34 +1,13 @@
-# fsharp-arguments
+# WoofWare.Myriad.Plugins
 
-Some helpers in [Myriad](https://github.com/MoiraeSoftware/myriad/) which might be useful for someone writing an argument parser.
+Some helpers in [Myriad](https://github.com/MoiraeSoftware/myriad/) which might be useful.
 
-## `RemoveOptions`
+These are currently somewhat experimental, and I personally am their primary customer.
+The `RemoveOptions` generator in particular is extremely half-baked.
 
-Takes a record like this:
-
-```fsharp
-type Foo =
-    {
-        A : int option
-        B : string
-        C : float list
-    }
-```
-
-and stamps out a record like this:
-
-```fsharp
-[<RequireQualifiedAccess>]
-module Foo =
-    type Short =
-        {
-            A : int
-            B : string
-            C : float list
-        }
-```
-
-(This is a proof of concept. It would be better to somehow disambiguate the module name.)
+Currently implemented:
+* `JsonParse` (to stamp out `jsonParse : JsonNode -> 'T` methods);
+* `RemoveOptions` (to strip `option` modifiers from a type).
 
 ## `JsonParse`
 
@@ -86,3 +65,66 @@ module JsonRecordType =
         let A = node.["a"].AsValue().GetValue<int>()
         { A = A; B = B; C = C; D = D }
 ```
+
+### What's the point?
+
+`System.Text.Json`, in a `PublishAot` context, relies on C# source generators.
+The default reflection-heavy implementations have the necessary code trimmed away, and result in a runtime exception.
+But C# source generators [are entirely unsupported in F#](https://github.com/dotnet/fsharp/issues/14300).
+
+This Myriad generator expects you to use `System.Text.Json` to construct a `JsonNode`, and then the generator takes over to construct a strongly-typed object.
+
+### Limitations
+
+This source generator is enough for what I first wanted to use it for.
+However, there is *far* more that could be done.
+
+* Make it possible to give an exact format and cultural info in date and time parsing.
+* Make it possible to reject parsing if extra fields are present.
+* Rather than just throwing `NullReferenceException`, print out the field name that failed.
+* Generally support all the `System.Text.Json` attributes.
+
+## `RemoveOptions`
+
+Takes a record like this:
+
+```fsharp
+type Foo =
+    {
+        A : int option
+        B : string
+        C : float list
+    }
+```
+
+and stamps out a record like this:
+
+```fsharp
+[<RequireQualifiedAccess>]
+module Foo =
+    type Short =
+        {
+            A : int
+            B : string
+            C : float list
+        }
+```
+
+### What's the point?
+
+The motivating example is argument parsing.
+An argument parser naturally wants to express "the user did not supply this, so I will provide a default".
+But it's not a very ergonomic experience for the programmer to deal with all these options,
+so this Myriad generator stamps out a type *without* any options, and also stamps out an appropriate constructor function.
+
+### Limitations
+
+This generator is *far* from where I want it, because I haven't really spent any time on it.
+* It really wants to be able to recurse into the types within the record, to strip options from them.
+* It needs some sort of attribute to mark a field as *not* receiving this treatment.
+* What do we do about discriminated unions?
+
+# Detailed examples
+
+See the tests.
+For example, [PureGymDto.fs](./ConsumePlugin/PureGymDto.fs) is a real-world set of DTOs.