Add documentation in README.md

Author: GigsD4X

README.md

@@ -1,2 +1,96 @@
-# RBX-Try-Library
-A library for controlling the flow of error-prone, interdependent functions.
+# RBX.Lua Try Library
+A library for controlling the flow of error-prone, interdependent functions. [Get a built module on Roblox here.](https://www.roblox.com/library/987135020/Try-Library-from-F3X)
+
+## How to use
+Include the library's Try function by requiring the module.
+
+```lua
+local Try = require(TryLibrary)
+```
+
+### Try(Function, Arguments...) → Attempt
+This function attempts calling `Function` with the given list of `Arguments...`, and returns an `Attempt`, which :Then and :Catch methods can be chained to.
+
+### Attempt:Then(Function `Callback`) → Attempt
+This method takes a callback of the form `Variant Callback(ReturnValues...)`, and calls it **if the attempt succeeded**, with `ReturnValues...` being the list of values returned in the attempt. The attempt is then returned for chaining.
+
+If the first value in `ReturnValues...` is an `Attempt`, it will be executed and the method will process its return values. This allows for chaining, such as in:
+
+```lua
+Try(Wait, 0.1)
+
+    -- Try hashing the time
+    :Then(function (Delta, ElapsedTime)
+        return Try(Game.HttpService.GetAsync, Game.HttpService, 'http://md5.jsontest.com/?text=' .. Delta)
+    end)
+
+    -- Try decoding the response
+    :Then(function (RawResponse)
+        return Try(Game.HttpService.JSONDecode, Game.HttpService, RawResponse)
+    end)
+
+    -- Print the decoded response data
+    :Then(function (Response)
+        print('Input:', Response.original, '\nMD5:', Response.md5)
+    end)
+```
+
+### Attempt:Catch([String `Predicates...`], Function `Callback`) → Attempt
+This method takes a callback of the form `Variant Callback(String Error, String Stack, Attempt FailedAttempt)`, and calls it **if the attempt had an error**. Errors can be optionally filtered by providing a list of [patterns which the error should match](http://wiki.roblox.com/index.php?title=String_pattern#Simple_matching), otherwise all errors are caught by the function. Once an attempt's error is caught, it will not be caught by the next chained :Catch method, unless `Callback` itself has an error. The attempt is then returned for chaining.
+
+If the first returned value from the attempt is an `Attempt`, it will be executed and the method will process its errors.
+
+```lua
+Try(Game.HttpService.GetAsync, Game.HttpService, 'http://google.com/fakeurl')
+    :Then(function (Data)
+        print('Found', Data)
+    end)
+
+    -- Catch when the URL doesn't exist
+    :Catch('HTTP 404', function (Error, Stack, Attempt)
+        warn('Not found, error:', Error)
+    end)
+
+    -- Catch any other error
+    :Catch(function (Error, Stack, Attempt)
+        warn('Unknown error:', Error)
+    end)
+```
+
+### Attempt:Retry() → Attempt
+This method retries the attempt if it failed, and executes any methods that were chained to it. `Attempt.RetryCount` is incremented each time the attempt is retried, and is reset if a retry succeeds.
+
+You can use this method in combination with an attempt's :Catch method to retry a sequence of interdependent function calls that fail, and even limit the number of, or space out, retries. For example:
+
+```lua
+Try(Game.HttpService.GetAsync, Game.HttpService, 'http://httpstat.us/503')
+    :Then(function (Data)
+        print('Found', Data)
+    end)
+
+    -- Catch when the server is having issues and retry
+    :Catch('HTTP 503', 'Timeout was reached', function (Error, Stack, Attempt)
+
+        -- Limit the number of retries to 3
+        if Attempt.RetryCount < 3 then
+
+            -- Space out each retry
+            local BackoffTime = Attempt.RetryCount * 3 + 3
+            warn('Retrying in', BackoffTime, 'seconds...')
+            wait(BackoffTime)
+
+            -- Retry the attempt
+            return Attempt:Retry()
+
+        -- Give up if retry limit reached
+        else
+            warn('Failed')
+        end
+
+    end)
+
+    -- Catch any other errors
+    :Catch(function (Error, Stack, Attempt)
+        warn('Unknown error:', Error)
+    end)
+```