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diff --git a/src/040-deriving-types-from-values/112-create-an-enum-from-as-const-object.problem.ts b/src/040-deriving-types-from-values/112-create-an-enum-from-as-const-object.problem.ts
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diff --git a/src/040-deriving-types-from-values/114-should-i-use-enums-or-as-const.problem.ts b/src/040-deriving-types-from-values/114-should-i-use-enums-or-as-const.problem.ts
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diff --git a/src/040-deriving-types-from-values/plan.md b/src/040-deriving-types-from-values/plan.md
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@@ -0,0 +1,34 @@
+# Title
+
+Deriving types from values
+
+## Exercises
+
+LEARNING GOAL: Understand the type world and the runtime world.
+CONFUSION: Can I create runtime values from types?
+LEARNING GOAL: Understand the `typeof` keyword.
+CONFUSION: Is this the same as the JavaScript keyword?
+
+LEARNING GOAL: You can only create types from runtime values, not the other way around.
+
+LEARNING GOAL: Use `ReturnType` to get the return type of a function.
+NOTEWORTHY: This is really good for extracting the return value of a third-party function.
+
+LEARNING GOAL: Use `Parameters` to get the parameters of a function.
+
+LEARNING GOAL: Understand the `keyof` keyword
+CONFUSION: Why do we have to do `keyof typeof` instead of just `keyof`?
+
+LEARNING GOAL: Understand indexed access types
+CONFUSION: Why can't I just use `.name` instead of `['name']`?
+
+LEARNING GOAL: Understand that you can pass unions into indexed access types.
+
+LEARNING GOAL: Understand that you can pass `keyof` into an indexed access type.
+
+LEARNING GOAL: Create an enum from an `as const` object.
+
+LEARNING GOAL: Create an enum from an `as const` array.
+LEARNING GOAL: Understand the `T[number]` syntax.
+
+CONFUSION: Should I use enums, or 'as const' objects?