commit e3512d887df41a8162c3e361171c04beca08415b
Author: Tom Stejskal <tom.stejskal@gmail.com>
Date:   Mon Nov 19 20:09:43 2018 +0100

    Fix Map.!: given key is not an element in the map

diff --git a/compiler/src/Elm/Compiler/Type/Extract.hs b/compiler/src/Elm/Compiler/Type/Extract.hs
index 1aafe1d4..99763392 100644
--- a/compiler/src/Elm/Compiler/Type/Extract.hs
+++ b/compiler/src/Elm/Compiler/Type/Extract.hs
@@ -10,6 +10,7 @@ module Elm.Compiler.Type.Extract
 
 
 import Data.Map ((!))
+import qualified Data.Map as Map
 import qualified Data.Maybe as Maybe
 import qualified Data.Set as Set
 
@@ -134,11 +135,15 @@ extractUnion interfaces (Opt.Global home name) =
     else
       let
         pname = toPublicName home name
-        unions = I._unions (interfaces ! home)
+        maybeUnions = I._unions <$> Map.lookup home interfaces
       in
-      case I.toUnionInternals (unions ! name) of
-        Can.Union vars ctors _ _ ->
-          T.Union pname vars <$> traverse extractCtor ctors
+      case Map.lookup name =<< maybeUnions of
+        Just union ->
+          case I.toUnionInternals union of
+            Can.Union vars ctors _ _ ->
+              T.Union pname vars <$> traverse extractCtor ctors
+        Nothing ->
+          return $ T.Union pname [] []
 
 
 extractCtor :: Can.Ctor -> Extractor (N.Name, [T.Type])
719dbcd8ea5c0e90b187a738'>commit</a><a href='/guix/diff/tests/graph.scm?id=1e6bd256a3d52e41719dbcd8ea5c0e90b187a738'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/graph.scm'>
<input type='hidden' name='id' value='1e6bd256a3d52e41719dbcd8ea5c0e90b187a738'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=1e6bd256a3d52e41719dbcd8ea5c0e90b187a738'>root</a>/<a href='/guix/log/tests?id=1e6bd256a3d52e41719dbcd8ea5c0e90b187a738'>tests</a>/<a href='/guix/log/tests/graph.scm?id=1e6bd256a3d52e41719dbcd8ea5c0e90b187a738'>graph.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/graph.scm?id=1e6bd256a3d52e41719dbcd8ea5c0e90b187a738&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-10-20 16:30:15 +0200'>2020-10-20</span></td><td><a href='/guix/commit/tests/graph.scm?id=a9fd59dbd2d32e08c9479ac026b99b5c1dbbb0db'>graph: Adjust test for recent OCaml changes.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-05-22 01:29:39 +0200'>2020-05-22</span></td><td><a href='/guix/commit/tests/graph.scm?id=ce0be5675b702b2ff89aed1772ebb42af4150243'>packages: Introduce &lt;content-hash&gt; and use it in &lt;origin&gt;.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-05-11 23:30:55 +0200'>2020-05-11</span></td><td><a href='/guix/commit/tests/graph.scm?id=36c2192414dfcc43db767106cede2cc1d0e6e556'>graph: Add 'shortest-path'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-05-11 23:30:55 +0200'>2020-05-11</span></td><td><a href='/guix/commit/tests/graph.scm?id=724020213664239ec5c92d04f5fee44c25408a7f'>graph: reference/referrer node types work with graph traversal.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-02-05 16:18:58 +0100'>2020-02-05</span></td><td><a href='/guix/commit/tests/graph.scm?id=312df1d40cf2d61fc96b32efedc16d958718fc48'>tests: Adjust reverse-bag graph test to recent OCaml changes.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-03-23 23:16:55 +0100'>2019-03-23</span></td><td><a href='/guix/commit/tests/graph.scm?id=8c14f7f8a7ab0722bf4c9f92fd28ae85514d564f'>Merge branch 'staging' into core-updates</a></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-03-23 18:15:36 +0100'>2019-03-23</span></td><td><a href='/guix/commit/tests/graph.scm?id=2b81eac01e5828c6fce61b3cafc0f78e7a0ab891'>graph: Add the 'reverse-bag' graph.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-09-22 22:40:12 +0200'>2018-09-22</span></td><td><a href='/guix/commit/tests/graph.scm?id=a2b2070b679ff7e92d856c7d6775f5f67ce4792d'>bootstrap: %bootstrap-inputs: Wrap input lists into thunks.</a><span class='msg-avail'>...</span></td><td>Jan Nieuwenhuizen</td></tr>