feat(question): add type-challenges#25747 - IsNegativeNumber (type-ch…

…allenges#25748)

Co-authored-by: andrew jarrett <15133992+ahrjarrett@users.noreply.github.com>

questions/25747-hard-isnegativenumber/README.md

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+Sometimes when working with numeric literals, we need to rule out (or enforce) that the provided number is a positive integer.
+
+To do that, we first need a way to tell if the number is negative.
+
+Write a type-level function `IsNegativeNumber` that accepts a number `N` and returns:
+
+- `true` if `N` is negative
+- `false` if `N` is positive
+- `false` if `N` is `0`, 
+- `never` if `N` is `number`
+- `never` if `N` is a union

questions/25747-hard-isnegativenumber/info.yml

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+difficulty: hard
+title: IsNegativeNumber
+tags: number, template literal
+author:
+  github: ahrjarrett
+  name: andrew jarrett
+

questions/25747-hard-isnegativenumber/template.ts

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+type IsNegativeNumber<T extends number> = any

questions/25747-hard-isnegativenumber/test-cases.ts

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+import type { Equal, Expect } from '@type-challenges/utils'
+
+type cases = [
+  Expect<Equal<IsNegativeNumber<0>, false>>,
+  Expect<Equal<IsNegativeNumber<number>, never>>,
+  Expect<Equal<IsNegativeNumber<-1 | -2>, never>>,
+  Expect<Equal<IsNegativeNumber<-1>, true>>,
+  Expect<Equal<IsNegativeNumber<-1.9>, true>>,
+  Expect<Equal<IsNegativeNumber<-100_000_000>, true>>,
+  Expect<Equal<IsNegativeNumber<1>, false>>,
+  Expect<Equal<IsNegativeNumber<1.9>, false>>,
+  Expect<Equal<IsNegativeNumber<100_000_000>, false>>,
+]