From 4c06c3f825130724b6bd7612dc2fdede29d6f701 Mon Sep 17 00:00:00 2001
From: "John J. Camilleri" <john@digitalgrammars.com>
Date: Tue, 16 Feb 2021 21:01:01 +0100
Subject: [PATCH] Add case for when pre is not followed by anything

---
 src/runtime/haskell/LPGF.hs | 3 ++-
 testsuite/lpgf/Pre.gf       | 1 +
 testsuite/lpgf/Pre.treebank | 5 +++++
 testsuite/lpgf/Pre.trees    | 2 ++
 testsuite/lpgf/PreCnc.gf    | 1 +
 5 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/runtime/haskell/LPGF.hs b/src/runtime/haskell/LPGF.hs
index 85be9d481..b7c170cdb 100644
--- a/src/runtime/haskell/LPGF.hs
+++ b/src/runtime/haskell/LPGF.hs
@@ -167,6 +167,7 @@ lin2string l = case l of
   LFSpace -> "" -- when encountered at beginning/end
   LFToken tok -> tok
   LFTuple [l] -> lin2string l
+  LFPre pts df -> lin2string df -- when encountered at end
   LFConcat (LFPre pts df) l2 -> lin2string $ LFConcat l1 l2
     where
       l2' = lin2string l2
@@ -177,7 +178,7 @@ lin2string l = case l of
   LFConcat LFCapit l2 -> let l = lin2string l2 in T.toUpper (T.take 1 l) `T.append` T.drop 1 l
   LFConcat LFAllCapit l2 -> let tks = T.words (lin2string l2) in T.unwords $ T.toUpper (head tks) : tail tks
   LFConcat l1 l2 -> T.unwords $ filter (not.T.null) [lin2string l1, lin2string l2]
-  x -> T.pack $ printf "[%s]" (show x)
+  x -> T.pack $ printf "<%s>" (show x)
 
 -- | List indexing with more verbose error messages
 (!!) :: (Show a) => [a] -> Int -> a
diff --git a/testsuite/lpgf/Pre.gf b/testsuite/lpgf/Pre.gf
index 5f8955d26..c1a015250 100644
--- a/testsuite/lpgf/Pre.gf
+++ b/testsuite/lpgf/Pre.gf
@@ -4,4 +4,5 @@ abstract Pre = {
     ant, dog: N ;
     a, the: Det ;
     mkS : Det -> N -> S;
+    detS : Det -> S;
 }
diff --git a/testsuite/lpgf/Pre.treebank b/testsuite/lpgf/Pre.treebank
index d7eedf79c..f2a9bb0ad 100644
--- a/testsuite/lpgf/Pre.treebank
+++ b/testsuite/lpgf/Pre.treebank
@@ -10,3 +10,8 @@ PreCnc: a dog
 Pre: mkS the dog
 PreCnc: the dog
 
+Pre: detS a
+PreCnc: a
+
+Pre: detS the
+PreCnc: the
diff --git a/testsuite/lpgf/Pre.trees b/testsuite/lpgf/Pre.trees
index c3ccbcd17..506b078cf 100644
--- a/testsuite/lpgf/Pre.trees
+++ b/testsuite/lpgf/Pre.trees
@@ -2,3 +2,5 @@ mkS a ant
 mkS the ant
 mkS a dog
 mkS the dog
+detS a
+detS the
diff --git a/testsuite/lpgf/PreCnc.gf b/testsuite/lpgf/PreCnc.gf
index 0a7927185..011e915dd 100644
--- a/testsuite/lpgf/PreCnc.gf
+++ b/testsuite/lpgf/PreCnc.gf
@@ -12,4 +12,5 @@ concrete PreCnc of Pre = {
     } } ;
     the = { s = "the" } ;
     mkS det n = { s = det.s ++ n.s } ;
+    detS det = { s = det.s } ;
 }