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+/MIGRATING.md

MIGRATING.md

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+# Migration guides
+
+## From v2 to v3
+
+No migrations needed with this version. We just added `rollup` as build tool and added the browser build in our examples.
+
+## From v1 to v2
+
+The first version of `categorize` used `yup` to validate users' input. With this, the library had two ways to categorize arrays:
+
+- a synchronous way using `categorizeSync` function;
+- and an asynchronous way using `categorize` function.
+
+With the second version, we removed `yup` library in order to become a zero-dependency library and did the validation manually.
+
+With this change we only have one way to categorize which is the sychronous way. So we removed the `categorizeSync` function and changed the `categorize` function to become a synchronous one.
+
+### Usage from v1
+
+```js
+// asynchronous way
+const asyncResult = await categorize(animals, categories);
+// synchronous way
+const syncResult = categorizeSync(animals, categories);
+```
+
+### Usage from v2
+
+```js
+const result = categorize(animals, categories);
+```