POC pattern for converting switches to functions

.grit/patterns/SwitchToFunction.md

@@ -0,0 +1,32 @@
+# Prefer early returns
+
+```
+language js
+
+[
+    `let $var`,
+    SwitchStatement(cases=$cases, discriminant=$disc)
+] => `const $var = $func($disc)` where {
+    // note how the name for this is not present in the original, but the LLM guesses it effectively
+    $input = guess(hint="Input name", fallback="input")
+    $tests = []
+    // TODO: we need `all` not `some` (use case for map?)
+    $cases <: some bubble($tests) SwitchCase(test=$test, consequent=$dec) where {
+        $return = `null`
+        $exp = []
+        $dec <: some bubble($exp, $return, $var) $x where {
+            $x <: not BreakStatement()
+            if ($x <: `$var = $val`) {
+                $return = $val
+            } else {
+                $exp = [...$exp, $x]
+            }
+        }
+        $tests = [...$tests, `if ($input === $test) { $exp; return $return; }`]
+    }
+    $func = `($input) => {
+        $tests
+        return nice;
+    }`
+}
+```