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System.ValueType F# snippets #8073

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10 changes: 10 additions & 0 deletions snippets/fsharp/System/ValueType/Equals/fs.fsproj
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<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net6.0</TargetFramework>
</PropertyGroup>

<ItemGroup>
<Compile Include="source.fs" />
</ItemGroup>
</Project>
14 changes: 14 additions & 0 deletions snippets/fsharp/System/ValueType/Equals/source.fs
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//<snippet1>
type Complex() =
member val m_Re = 0. with get, set
member val m_Im = 0. with get, set

override this.Equals(ob) =
match ob with
| :? Complex as c ->
this.m_Re = c.m_Re && this.m_Im = c.m_Im
| _ -> false

override this.GetHashCode() =
this.m_Re.GetHashCode() ^^^ this.m_Im.GetHashCode()
//</snippet1>
95 changes: 95 additions & 0 deletions snippets/fsharp/System/ValueType/Overview/example1.fs
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// <Snippet1>
open System
open System.Numerics

module Utility =
type NumericRelationship =
| GreaterThan = 1
| EqualTo = 0
| LessThan = -1

let isInteger (value: ValueType) =
match value with
| :? sbyte | :? int16 | :? int32 | :? int64
| :? byte | :? uint16 | :? uint32
| :? uint64 | :? bigint -> true
| _ -> false

let isFloat (value: ValueType) =
match value with
| :? float32 | :? float | :? decimal -> true
| _ -> false

let tryToBigInt (value: ValueType) =
match value with
| :? sbyte as v -> bigint v |> Some
| :? int16 as v -> bigint v |> Some
| :? int32 as v -> bigint v |> Some
| :? int64 as v -> bigint v |> Some
| :? byte as v -> bigint v |> Some
| :? uint16 as v -> bigint v |> Some
| :? uint32 as v -> bigint v |> Some
| :? uint64 as v -> bigint v |> Some
| :? float32 as v -> bigint v |> Some
| _ -> None

let isNumeric (value: ValueType) =
isInteger value || isFloat value

let compare (value1: ValueType) (value2: ValueType) =
if isNumeric value1 |> not then
invalidArg "value1" "value1 is not a number."
elif isNumeric value2 |> not then
invalidArg "value2" "value2 is not a number."

// Use BigInteger as common integral type
match tryToBigInt value1, tryToBigInt value2 with
| Some bigint1, Some bigint2 ->
BigInteger.Compare(bigint1, bigint2) |> enum<NumericRelationship>

// At least one value is floating point use Double.
| _ ->
let dbl1 =
try
Convert.ToDouble value1
with
| :? OverflowException ->
printfn "value1 is outside the range of a Double."
0.
| _ -> 0.

let dbl2 =
try
Convert.ToDouble value2
with
| :? OverflowException ->
printfn "value2 is outside the range of a Double."
0.
| _ -> 0.

dbl1.CompareTo dbl2 |> enum<NumericRelationship>
// </Snippet1>

// <Snippet2>
printfn $"{Utility.isNumeric 12}"
printfn $"{Utility.isNumeric true}"
printfn $"{Utility.isNumeric 'c'}"
printfn $"{Utility.isNumeric (DateTime(2012, 1, 1))}"
printfn $"{Utility.isInteger 12.2}"
printfn $"{Utility.isInteger 123456789}"
printfn $"{Utility.isFloat true}"
printfn $"{Utility.isFloat 12.2}"
printfn $"{Utility.isFloat 12}"
printfn $"{12.1} {Utility.compare 12.1 12} {12}"
// The example displays the following output:
// True
// False
// False
// False
// False
// True
// False
// True
// False
// 12.1 GreaterThan 12
// </Snippet2>
10 changes: 10 additions & 0 deletions snippets/fsharp/System/ValueType/Overview/fs.fsproj
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<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net6.0</TargetFramework>
</PropertyGroup>

<ItemGroup>
<Compile Include="example1.fs" />
</ItemGroup>
</Project>
23 changes: 23 additions & 0 deletions snippets/fsharp/System/ValueType/ToString/ToString2.fs
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// <Snippet1>
namespace Corporate.EmployeeObjects

[<Struct>]
type EmployeeA =
val mutable Name : string

[<Struct>]
type EmployeeB =
val mutable Name : string
override this.ToString() =
this.Name

module Example =
let empA = EmployeeA(Name="Robert")
printfn $"{empA}"

let empB = EmployeeB(Name="Robert")
printfn $"{empB}"
// The example displays the following output:
// Corporate.EmployeeObjects.EmployeeA
// Robert
// </Snippet1>
10 changes: 10 additions & 0 deletions snippets/fsharp/System/ValueType/ToString/fs.fsproj
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<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net6.0</TargetFramework>
</PropertyGroup>

<ItemGroup>
<Compile Include="ToString2.fs" />
</ItemGroup>
</Project>
5 changes: 5 additions & 0 deletions xml/System/ValueType.xml
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Expand Up @@ -66,11 +66,13 @@
Aside from serving as the base class for value types in the .NET Framework, the <xref:System.ValueType> structure is generally not used directly in code. However, it can be used as a parameter in method calls to restrict possible arguments to value types instead of all objects, or to permit a method to handle a number of different value types. The following example illustrates how <xref:System.ValueType> prevents reference types from being passed to methods. It defines a class named `Utility` that contains four methods: `IsNumeric`, which indicates whether its argument is a number; `IsInteger`, which indicates whether its argument is an integer; `IsFloat`, which indicates whether its argument is a floating-point number; and `Compare`, which indicates the relationship between two numeric values. In each case, the method parameters are of type <xref:System.ValueType>, and reference types are prevented from being passed to the methods.

:::code language="csharp" source="~/snippets/csharp/System/ValueType/Overview/example1.cs" id="Snippet1":::
:::code language="fsharp" source="~/snippets/fsharp/System/ValueType/Overview/example1.fs" id="Snippet1":::
:::code language="vb" source="~/snippets/visualbasic/VS_Snippets_CLR_System/system.valuetype.structure/vb/example1.vb" id="Snippet1":::

The following example illustrates calls to the methods of the `Utility` class.

:::code language="csharp" source="~/snippets/csharp/System/ValueType/Overview/example1.cs" id="Snippet2":::
:::code language="fsharp" source="~/snippets/fsharp/System/ValueType/Overview/example1.fs" id="Snippet2":::
:::code language="vb" source="~/snippets/visualbasic/VS_Snippets_CLR_System/system.valuetype.structure/vb/example1.vb" id="Snippet2":::

]]></format>
Expand Down Expand Up @@ -196,6 +198,7 @@

:::code language="cpp" source="~/snippets/cpp/VS_Snippets_CLR/ValueType.Equals Example/CPP/source.cpp" id="Snippet1":::
:::code language="csharp" source="~/snippets/csharp/System/ValueType/Equals/source.cs" id="Snippet1":::
:::code language="fsharp" source="~/snippets/fsharp/System/ValueType/Equals/source.fs" id="Snippet1":::
:::code language="vb" source="~/snippets/visualbasic/VS_Snippets_CLR/ValueType.Equals Example/VB/source.vb" id="Snippet1":::

]]></format>
Expand Down Expand Up @@ -266,6 +269,7 @@

:::code language="cpp" source="~/snippets/cpp/VS_Snippets_CLR/ValueType.Equals Example/CPP/source.cpp" id="Snippet1":::
:::code language="csharp" source="~/snippets/csharp/System/ValueType/Equals/source.cs" id="Snippet1":::
:::code language="fsharp" source="~/snippets/fsharp/System/ValueType/Equals/source.fs" id="Snippet1":::
:::code language="vb" source="~/snippets/visualbasic/VS_Snippets_CLR/ValueType.Equals Example/VB/source.vb" id="Snippet1":::

]]></format>
Expand Down Expand Up @@ -322,6 +326,7 @@
Value types defined by the `struct` keyword in C# and the `Structure`...`End Structure` construct in Visual Basic typically override the <xref:System.ValueType.ToString%2A?displayProperty=nameWithType> method to provide a more meaningful string representation of the value type. The following example illustrates the difference. It defines two value types, `EmployeeA` and `EmployeeB`, creates an instance of each, and calls its `ToString` method. Because the `EmployeeA` structure does not override the <xref:System.ValueType.ToString%2A?displayProperty=nameWithType> method, it displays only the fully qualified type name. The `EmployeeB.ToString` method, on the other hand, provides meaningful information about the object.

:::code language="csharp" source="~/snippets/csharp/System/ValueType/ToString/ToString2.cs" interactive="try-dotnet" id="Snippet1":::
:::code language="fsharp" source="~/snippets/fsharp/System/ValueType/ToString/ToString2.fs" id="Snippet1":::
:::code language="vb" source="~/snippets/visualbasic/VS_Snippets_CLR_System/System.ValueType.ToString/vb/ToString2.vb" id="Snippet1":::

Note that, although enumeration types are also value types, they derive from the <xref:System.Enum> class, which overrides <xref:System.ValueType.ToString%2A?displayProperty=nameWithType>.
Expand Down