Look under . for function name on lhs

Need this to rule out some ambiguous names. Fixes #204.

docs/reference/envvars.rst

@@ -0,0 +1,7 @@
+.. _ref-sect-envvars:
+
+*********************
+Environment Variables
+*********************
+
+[TODO: Fill in the environment variables recognised by Idris 2]

docs/reference/index.rst

@@ -17,3 +17,4 @@ This is a placeholder, to get set up with readthedocs.
    :maxdepth: 1
 
    packages
+   envvars

src/TTImp/Elab/Ambiguity.idr

@@ -262,6 +262,7 @@ pruneByType env target alts
                 -- if there's any concrete matches, drop the non-concrete
                 -- matches marked as '%allow_overloads' from the possible set
                    then do keep <- filterCore (notOverloadable defs) matches
+                           log 10 $ "Keep " ++ show keep
                            pure (map snd keep)
                    else pure (map snd matches)
          if isNil res

src/TTImp/TTImp.idr

@@ -562,6 +562,7 @@ getFn (IApp _ f arg) = getFn f
 getFn (IWithApp _ f arg) = getFn f
 getFn (IImplicitApp _ f _ _) = getFn f
 getFn (IAs _ _ _ f) = getFn f
+getFn (IMustUnify _ _ f) = getFn f
 getFn f = f
 
 -- Everything below is TTC instances

tests/Main.idr

@@ -72,7 +72,7 @@ idrisTests
        -- Records, access and dependent update
        "record001", "record002",
        -- Miscellaneous regressions
-       "reg001", "reg002", "reg003", "reg004", "reg005",
+       "reg001", "reg002", "reg003", "reg004", "reg005", "reg006",
        -- Totality checking
        "total001", "total002", "total003", "total004", "total005",
        "total006",

tests/idris2/reg006/Cmd.idr

@@ -0,0 +1,20 @@
+data MyCmd : Type -> Type where
+  Display : String -> MyCmd ()
+  Input : MyCmd String
+
+  Pure : ty -> MyCmd ty
+  (>>=) : MyCmd a -> (a -> MyCmd b) -> MyCmd b
+
+runMyCmd : MyCmd a -> IO a
+runMyCmd (Display str) = putStrLn str
+runMyCmd Input = do str <- getLine
+                    pure str
+runMyCmd (Pure x) = pure x
+runMyCmd (c >>= f) = do res <- runMyCmd c
+                        runMyCmd (f res)
+
+myCmdTest : MyCmd ()
+myCmdTest = do Display "Hello"
+               x <- Input
+               Display x
+               Pure ()

tests/idris2/reg006/expected

@@ -0,0 +1 @@
+1/1: Building Cmd (Cmd.idr)

tests/idris2/reg006/run

@@ -0,0 +1,3 @@
+$1 --check Cmd.idr
+
+rm -rf build