feat: add Form.disableIf

[Fable.Form][Fable.Form.Simple.Bulma]

Fix #45

packages/Fable.Form.Simple.Bulma/Form.fs

@@ -80,6 +80,15 @@ module Form =
 
         Base.disable form
 
+    /// <summary>
+    /// Disable a form based on a condition
+    /// </summary>
+    /// <param name="condition">The condition to check</param>
+    /// <param name="form">The form to disable</param>
+    /// <returns>A new form which has been marked as disabled if the condition is <c>true</c></returns>
+    let disableIf (condition: bool) (form: Form<'Values, 'A>) : Form<'Values, 'A> =
+        Base.disableIf condition form
+
     /// <summary>
     /// Fill a form <c>andThen</c> fill another one.
     ///

packages/Fable.Form/Base.fs

@@ -314,6 +314,22 @@ let disable (form: Form<'Values, 'Output, 'Field>) : Form<'Values, 'Output, 'Fie
         }
     )
 
+/// <summary>
+/// Disable a form based on a condition
+/// </summary>
+/// <param name="condition">The condition to check</param>
+/// <param name="form">The form to disable</param>
+/// <returns>A new form which has been marked as disabled if the condition is <c>true</c></returns>
+let disableIf
+    (condition: bool)
+    (form: Form<'Values, 'Output, 'Field>)
+    : Form<'Values, 'Output, 'Field>
+    =
+    if condition then
+        disable form
+    else
+        form
+
 /// <summary>
 /// Transform the 'output' of a form
 ///