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<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE ConstraintKinds #-}</span>
<a name="line-2"></a><span class='hs-comment'>{-# LANGUAGE DataKinds #-}</span>
<a name="line-3"></a><span class='hs-comment'>{-# LANGUAGE FlexibleContexts #-}</span>
<a name="line-4"></a><span class='hs-comment'>{-# LANGUAGE OverloadedStrings #-}</span>
<a name="line-5"></a><span class='hs-comment'>{-# LANGUAGE TypeFamilies #-}</span>
<a name="line-6"></a>
<a name="line-7"></a><span class='hs-comment'>-- | This module lets you implement 'Server's for defined APIs. You'll</span>
<a name="line-8"></a><span class='hs-comment'>-- most likely just need 'serve'.</span>
<a name="line-9"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Servant</span><span class='hs-varop'>.</span><span class='hs-conid'>Server</span>
<a name="line-10"></a> <span class='hs-layout'>(</span> <span class='hs-comment'>-- * Run a wai application from an API</span>
<a name="line-11"></a> <span class='hs-varid'>serve</span>
<a name="line-12"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>serveWithContext</span>
<a name="line-13"></a>
<a name="line-14"></a> <span class='hs-layout'>,</span> <span class='hs-comment'>-- * Construct a wai Application from an API</span>
<a name="line-15"></a> <span class='hs-varid'>toApplication</span>
<a name="line-16"></a>
<a name="line-17"></a> <span class='hs-layout'>,</span> <span class='hs-comment'>-- * Handlers for all standard combinators</span>
<a name="line-18"></a> <span class='hs-conid'>HasServer</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-19"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Server</span>
<a name="line-20"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Handler</span>
<a name="line-21"></a>
<a name="line-22"></a> <span class='hs-comment'>-- * Debugging the server layout</span>
<a name="line-23"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>layout</span>
<a name="line-24"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>layoutWithContext</span>
<a name="line-25"></a>
<a name="line-26"></a> <span class='hs-comment'>-- * Enter</span>
<a name="line-27"></a> <span class='hs-comment'>-- $enterDoc</span>
<a name="line-28"></a>
<a name="line-29"></a> <span class='hs-comment'>-- ** Basic functions and datatypes</span>
<a name="line-30"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>enter</span>
<a name="line-31"></a> <span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-conop'>:~></span><span class='hs-layout'>)</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-32"></a> <span class='hs-comment'>-- ** `Nat` utilities</span>
<a name="line-33"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>liftNat</span>
<a name="line-34"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>runReaderTNat</span>
<a name="line-35"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>evalStateTLNat</span>
<a name="line-36"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>evalStateTSNat</span>
<a name="line-37"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>logWriterTLNat</span>
<a name="line-38"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>logWriterTSNat</span>
<a name="line-39"></a> <span class='hs-comment'>-- ** Functions based on <https://hackage.haskell.org/package/mmorph mmorph></span>
<a name="line-40"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>hoistNat</span>
<a name="line-41"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>embedNat</span>
<a name="line-42"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>squashNat</span>
<a name="line-43"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>generalizeNat</span>
<a name="line-44"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>tweakResponse</span>
<a name="line-45"></a>
<a name="line-46"></a> <span class='hs-comment'>-- * Context</span>
<a name="line-47"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Context</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-48"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>HasContextEntry</span><span class='hs-layout'>(</span><span class='hs-varid'>getContextEntry</span><span class='hs-layout'>)</span>
<a name="line-49"></a> <span class='hs-comment'>-- ** NamedContext</span>
<a name="line-50"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>NamedContext</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-51"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>descendIntoNamedContext</span>
<a name="line-52"></a>
<a name="line-53"></a> <span class='hs-comment'>-- * Basic Authentication</span>
<a name="line-54"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>BasicAuthCheck</span><span class='hs-layout'>(</span><span class='hs-conid'>BasicAuthCheck</span><span class='hs-layout'>,</span> <span class='hs-varid'>unBasicAuthCheck</span><span class='hs-layout'>)</span>
<a name="line-55"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>BasicAuthResult</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-56"></a>
<a name="line-57"></a> <span class='hs-comment'>-- * General Authentication</span>
<a name="line-58"></a> <span class='hs-comment'>-- , AuthHandler(unAuthHandler)</span>
<a name="line-59"></a> <span class='hs-comment'>-- , AuthServerData</span>
<a name="line-60"></a> <span class='hs-comment'>-- , mkAuthHandler</span>
<a name="line-61"></a>
<a name="line-62"></a> <span class='hs-comment'>-- * Default error type</span>
<a name="line-63"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>ServantErr</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-64"></a> <span class='hs-comment'>-- ** 3XX</span>
<a name="line-65"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err300</span>
<a name="line-66"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err301</span>
<a name="line-67"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err302</span>
<a name="line-68"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err303</span>
<a name="line-69"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err304</span>
<a name="line-70"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err305</span>
<a name="line-71"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err307</span>
<a name="line-72"></a> <span class='hs-comment'>-- ** 4XX</span>
<a name="line-73"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err400</span>
<a name="line-74"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err401</span>
<a name="line-75"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err402</span>
<a name="line-76"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err403</span>
<a name="line-77"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err404</span>
<a name="line-78"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err405</span>
<a name="line-79"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err406</span>
<a name="line-80"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err407</span>
<a name="line-81"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err409</span>
<a name="line-82"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err410</span>
<a name="line-83"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err411</span>
<a name="line-84"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err412</span>
<a name="line-85"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err413</span>
<a name="line-86"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err414</span>
<a name="line-87"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err415</span>
<a name="line-88"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err416</span>
<a name="line-89"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err417</span>
<a name="line-90"></a> <span class='hs-comment'>-- ** 5XX</span>
<a name="line-91"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err500</span>
<a name="line-92"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err501</span>
<a name="line-93"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err502</span>
<a name="line-94"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err503</span>
<a name="line-95"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err504</span>
<a name="line-96"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>err505</span>
<a name="line-97"></a>
<a name="line-98"></a> <span class='hs-comment'>-- * Re-exports</span>
<a name="line-99"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Application</span>
<a name="line-100"></a>
<a name="line-101"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-102"></a>
<a name="line-103"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Proxy</span> <span class='hs-layout'>(</span><span class='hs-conid'>Proxy</span><span class='hs-layout'>)</span>
<a name="line-104"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Text</span> <span class='hs-layout'>(</span><span class='hs-conid'>Text</span><span class='hs-layout'>)</span>
<a name="line-105"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Network</span><span class='hs-varop'>.</span><span class='hs-conid'>Wai</span> <span class='hs-layout'>(</span><span class='hs-conid'>Application</span><span class='hs-layout'>)</span>
<a name="line-106"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Servant</span><span class='hs-varop'>.</span><span class='hs-conid'>Server</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span>
<a name="line-107"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Servant</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span><span class='hs-varop'>.</span><span class='hs-conid'>Enter</span>
<a name="line-108"></a>
<a name="line-109"></a>
<a name="line-110"></a><span class='hs-comment'>-- * Implementing Servers</span>
<a name="line-111"></a>
<a name="line-112"></a><a name="serve"></a><span class='hs-comment'>-- | 'serve' allows you to implement an API and produce a wai 'Application'.</span>
<a name="line-113"></a><span class='hs-comment'>--</span>
<a name="line-114"></a><span class='hs-comment'>-- Example:</span>
<a name="line-115"></a><span class='hs-comment'>--</span>
<a name="line-116"></a><span class='hs-comment'>-- > type MyApi = "books" :> Get '[JSON] [Book] -- GET /books</span>
<a name="line-117"></a><span class='hs-comment'>-- > :<|> "books" :> ReqBody Book :> Post '[JSON] Book -- POST /books</span>
<a name="line-118"></a><span class='hs-comment'>-- ></span>
<a name="line-119"></a><span class='hs-comment'>-- > server :: Server MyApi</span>
<a name="line-120"></a><span class='hs-comment'>-- > server = listAllBooks :<|> postBook</span>
<a name="line-121"></a><span class='hs-comment'>-- > where listAllBooks = ...</span>
<a name="line-122"></a><span class='hs-comment'>-- > postBook book = ...</span>
<a name="line-123"></a><span class='hs-comment'>-- ></span>
<a name="line-124"></a><span class='hs-comment'>-- > myApi :: Proxy MyApi</span>
<a name="line-125"></a><span class='hs-comment'>-- > myApi = Proxy</span>
<a name="line-126"></a><span class='hs-comment'>-- ></span>
<a name="line-127"></a><span class='hs-comment'>-- > app :: Application</span>
<a name="line-128"></a><span class='hs-comment'>-- > app = serve myApi server</span>
<a name="line-129"></a><span class='hs-comment'>-- ></span>
<a name="line-130"></a><span class='hs-comment'>-- > main :: IO ()</span>
<a name="line-131"></a><span class='hs-comment'>-- > main = Network.Wai.Handler.Warp.run 8080 app</span>
<a name="line-132"></a><span class='hs-comment'>--</span>
<a name="line-133"></a><span class='hs-definition'>serve</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>HasServer</span> <span class='hs-varid'>api</span> <span class='hs-chr'>'</span><span class='hs-conid'>[]</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Proxy</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Server</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Application</span>
<a name="line-134"></a><span class='hs-definition'>serve</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>serveWithContext</span> <span class='hs-varid'>p</span> <span class='hs-conid'>EmptyContext</span>
<a name="line-135"></a>
<a name="line-136"></a><a name="serveWithContext"></a><span class='hs-definition'>serveWithContext</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>HasServer</span> <span class='hs-varid'>api</span> <span class='hs-varid'>context</span><span class='hs-layout'>)</span>
<a name="line-137"></a> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Proxy</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Context</span> <span class='hs-varid'>context</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Server</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Application</span>
<a name="line-138"></a><span class='hs-definition'>serveWithContext</span> <span class='hs-varid'>p</span> <span class='hs-varid'>context</span> <span class='hs-varid'>server</span> <span class='hs-keyglyph'>=</span>
<a name="line-139"></a> <span class='hs-varid'>toApplication</span> <span class='hs-layout'>(</span><span class='hs-varid'>runRouter</span> <span class='hs-layout'>(</span><span class='hs-varid'>route</span> <span class='hs-varid'>p</span> <span class='hs-varid'>context</span> <span class='hs-layout'>(</span><span class='hs-varid'>emptyDelayed</span> <span class='hs-layout'>(</span><span class='hs-conid'>Route</span> <span class='hs-varid'>server</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-140"></a>
<a name="line-141"></a><a name="layout"></a><span class='hs-comment'>-- | The function 'layout' produces a textual description of the internal</span>
<a name="line-142"></a><span class='hs-comment'>-- router layout for debugging purposes. Note that the router layout is</span>
<a name="line-143"></a><span class='hs-comment'>-- determined just by the API, not by the handlers.</span>
<a name="line-144"></a><span class='hs-comment'>--</span>
<a name="line-145"></a><span class='hs-comment'>-- Example:</span>
<a name="line-146"></a><span class='hs-comment'>--</span>
<a name="line-147"></a><span class='hs-comment'>-- For the following API</span>
<a name="line-148"></a><span class='hs-comment'>--</span>
<a name="line-149"></a><span class='hs-comment'>-- > type API =</span>
<a name="line-150"></a><span class='hs-comment'>-- > "a" :> "d" :> Get '[JSON] NoContent</span>
<a name="line-151"></a><span class='hs-comment'>-- > :<|> "b" :> Capture "x" Int :> Get '[JSON] Bool</span>
<a name="line-152"></a><span class='hs-comment'>-- > :<|> "c" :> Put '[JSON] Bool</span>
<a name="line-153"></a><span class='hs-comment'>-- > :<|> "a" :> "e" :> Get '[JSON] Int</span>
<a name="line-154"></a><span class='hs-comment'>-- > :<|> "b" :> Capture "x" Int :> Put '[JSON] Bool</span>
<a name="line-155"></a><span class='hs-comment'>-- > :<|> Raw</span>
<a name="line-156"></a><span class='hs-comment'>--</span>
<a name="line-157"></a><span class='hs-comment'>-- we get the following output:</span>
<a name="line-158"></a><span class='hs-comment'>--</span>
<a name="line-159"></a><span class='hs-comment'>-- > /</span>
<a name="line-160"></a><span class='hs-comment'>-- > ├─ a/</span>
<a name="line-161"></a><span class='hs-comment'>-- > │ ├─ d/</span>
<a name="line-162"></a><span class='hs-comment'>-- > │ │ └─•</span>
<a name="line-163"></a><span class='hs-comment'>-- > │ └─ e/</span>
<a name="line-164"></a><span class='hs-comment'>-- > │ └─•</span>
<a name="line-165"></a><span class='hs-comment'>-- > ├─ b/</span>
<a name="line-166"></a><span class='hs-comment'>-- > │ └─ <capture>/</span>
<a name="line-167"></a><span class='hs-comment'>-- > │ ├─•</span>
<a name="line-168"></a><span class='hs-comment'>-- > │ ┆</span>
<a name="line-169"></a><span class='hs-comment'>-- > │ └─•</span>
<a name="line-170"></a><span class='hs-comment'>-- > ├─ c/</span>
<a name="line-171"></a><span class='hs-comment'>-- > │ └─•</span>
<a name="line-172"></a><span class='hs-comment'>-- > ┆</span>
<a name="line-173"></a><span class='hs-comment'>-- > └─ <raw></span>
<a name="line-174"></a><span class='hs-comment'>--</span>
<a name="line-175"></a><span class='hs-comment'>-- Explanation of symbols:</span>
<a name="line-176"></a><span class='hs-comment'>--</span>
<a name="line-177"></a><span class='hs-comment'>-- [@├@] Normal lines reflect static branching via a table.</span>
<a name="line-178"></a><span class='hs-comment'>--</span>
<a name="line-179"></a><span class='hs-comment'>-- [@a/@] Nodes reflect static path components.</span>
<a name="line-180"></a><span class='hs-comment'>--</span>
<a name="line-181"></a><span class='hs-comment'>-- [@─•@] Leaves reflect endpoints.</span>
<a name="line-182"></a><span class='hs-comment'>--</span>
<a name="line-183"></a><span class='hs-comment'>-- [@\<capture\>/@] This is a delayed capture of a path component.</span>
<a name="line-184"></a><span class='hs-comment'>--</span>
<a name="line-185"></a><span class='hs-comment'>-- [@\<raw\>@] This is a part of the API we do not know anything about.</span>
<a name="line-186"></a><span class='hs-comment'>--</span>
<a name="line-187"></a><span class='hs-comment'>-- [@┆@] Dashed lines suggest a dynamic choice between the part above</span>
<a name="line-188"></a><span class='hs-comment'>-- and below. If there is a success for fatal failure in the first part,</span>
<a name="line-189"></a><span class='hs-comment'>-- that one takes precedence. If both parts fail, the \"better\" error</span>
<a name="line-190"></a><span class='hs-comment'>-- code will be returned.</span>
<a name="line-191"></a><span class='hs-comment'>--</span>
<a name="line-192"></a><span class='hs-definition'>layout</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>HasServer</span> <span class='hs-varid'>api</span> <span class='hs-chr'>'</span><span class='hs-conid'>[]</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Proxy</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span>
<a name="line-193"></a><span class='hs-definition'>layout</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>layoutWithContext</span> <span class='hs-varid'>p</span> <span class='hs-conid'>EmptyContext</span>
<a name="line-194"></a>
<a name="line-195"></a><a name="layoutWithContext"></a><span class='hs-comment'>-- | Variant of 'layout' that takes an additional 'Context'.</span>
<a name="line-196"></a><span class='hs-definition'>layoutWithContext</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>HasServer</span> <span class='hs-varid'>api</span> <span class='hs-varid'>context</span><span class='hs-layout'>)</span>
<a name="line-197"></a> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Proxy</span> <span class='hs-varid'>api</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Context</span> <span class='hs-varid'>context</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span>
<a name="line-198"></a><span class='hs-definition'>layoutWithContext</span> <span class='hs-varid'>p</span> <span class='hs-varid'>context</span> <span class='hs-keyglyph'>=</span>
<a name="line-199"></a> <span class='hs-varid'>routerLayout</span> <span class='hs-layout'>(</span><span class='hs-varid'>route</span> <span class='hs-varid'>p</span> <span class='hs-varid'>context</span> <span class='hs-layout'>(</span><span class='hs-varid'>emptyDelayed</span> <span class='hs-layout'>(</span><span class='hs-conid'>FailFatal</span> <span class='hs-varid'>err501</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-200"></a>
<a name="line-201"></a><span class='hs-comment'>-- Documentation</span>
<a name="line-202"></a>
<a name="line-203"></a><span class='hs-comment'>-- $enterDoc</span>
<a name="line-204"></a><span class='hs-comment'>-- Sometimes our cherished `ExceptT` monad isn't quite the type you'd like for</span>
<a name="line-205"></a><span class='hs-comment'>-- your handlers. Maybe you want to thread some configuration in a @Reader@</span>
<a name="line-206"></a><span class='hs-comment'>-- monad. Or have your types ensure that your handlers don't do any IO. Enter</span>
<a name="line-207"></a><span class='hs-comment'>-- `enter`.</span>
<a name="line-208"></a><span class='hs-comment'>--</span>
<a name="line-209"></a><span class='hs-comment'>-- With `enter`, you can provide a function, wrapped in the `(:~>)` / `Nat`</span>
<a name="line-210"></a><span class='hs-comment'>-- newtype, to convert any number of endpoints from one type constructor to</span>
<a name="line-211"></a><span class='hs-comment'>-- another. For example</span>
<a name="line-212"></a><span class='hs-comment'>--</span>
<a name="line-213"></a><span class='hs-comment'>-- >>> import Control.Monad.Reader</span>
<a name="line-214"></a><span class='hs-comment'>-- >>> import qualified Control.Category as C</span>
<a name="line-215"></a><span class='hs-comment'>-- >>> type ReaderAPI = "ep1" :> Get '[JSON] Int :<|> "ep2" :> Get '[JSON] String</span>
<a name="line-216"></a><span class='hs-comment'>-- >>> let readerServer = return 1797 :<|> ask :: ServerT ReaderAPI (Reader String)</span>
<a name="line-217"></a><span class='hs-comment'>-- >>> let mainServer = enter (generalizeNat C.. (runReaderTNat "hi")) readerServer :: Server ReaderAPI</span>
<a name="line-218"></a><span class='hs-comment'>--</span>
<a name="line-219"></a>
<a name="line-220"></a><span class='hs-comment'>-- $setup</span>
<a name="line-221"></a><span class='hs-comment'>-- >>> import Servant.API</span>
<a name="line-222"></a><span class='hs-comment'>-- >>> import Servant.Server</span>
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