Separator between member and type annotation interpreted as operator

src/Compiler/Checking/CheckDeclarations.fs

@@ -178,7 +178,6 @@ module MutRecShapes =
 
    let iterTyconsWithEnv f1 env xs = iterWithEnv f1 (fun _env _x -> ()) (fun _env _x -> ()) (fun _env _x -> ()) env xs
 
-
 /// Indicates a declaration is contained in the given module 
 let ModuleOrNamespaceContainerInfo modref =
     ContainerInfo(Parent modref, Some(MemberOrValContainerInfo(modref, None, None, NoSafeInitInfo, [])))

src/Compiler/SyntaxTree/LexFilter.fs

@@ -1172,6 +1172,11 @@ type LexFilterImpl (
                             delayToken (pool.UseShiftedLocation(tokenTup, INFIX_AT_HAT_OP "^", 1, 0))
                             delayToken (pool.UseShiftedLocation(tokenTup, LESS res, 0, -1))
                             pool.Return tokenTup
+
+                        | INFIX_COMPARE_OP ">:" ->
+                            delayToken (pool.UseShiftedLocation(tokenTup, COLON, 1, 0))
+                            delayToken (pool.UseShiftedLocation(tokenTup, GREATER res, 0, -1))
+                            pool.Return tokenTup
                         // NOTE: this is "<@"
                         | LQUOTE ("<@ @>", false) ->
                             delayToken (pool.UseShiftedLocation(tokenTup, INFIX_AT_HAT_OP "@", 1, 0))

src/Compiler/lex.fsl

@@ -112,6 +112,10 @@ let checkExprOp (lexbuf:UnicodeLexing.Lexbuf) =
         deprecatedWithError (FSComp.SR.lexCharNotAllowedInOperatorNames(":")) lexbuf.LexemeRange
     if lexbuf.LexemeContains '$' then
         deprecatedWithError (FSComp.SR.lexCharNotAllowedInOperatorNames("$")) lexbuf.LexemeRange
+
+let checkExprGreaterColonOp (lexbuf:UnicodeLexing.Lexbuf) =
+    if lexbuf.LexemeContains '$' then
+        deprecatedWithError (FSComp.SR.lexCharNotAllowedInOperatorNames("$")) lexbuf.LexemeRange
 
 let unexpectedChar lexbuf =
     LEX_FAILURE (FSComp.SR.lexUnexpectedChar(lexeme lexbuf))
@@ -945,7 +949,9 @@ rule token (args: LexArgs) (skip: bool) = parse
 
  | ignored_op_char* ('@'|'^')                  op_char* { checkExprOp lexbuf; INFIX_AT_HAT_OP(lexeme lexbuf) }
 
- | ignored_op_char* ('=' | "!=" | '<' | '>' | '$')  op_char* { checkExprOp lexbuf; INFIX_COMPARE_OP(lexeme lexbuf) }
+ | ignored_op_char* ('=' | "!=" | '<' | '$')  op_char* { checkExprOp lexbuf; INFIX_COMPARE_OP(lexeme lexbuf) }
+
+ | ignored_op_char* ('>')  op_char* { checkExprGreaterColonOp lexbuf; INFIX_COMPARE_OP(lexeme lexbuf) }
 
  | ignored_op_char* ('&')                      op_char* { checkExprOp lexbuf; INFIX_AMP_OP(lexeme lexbuf) }
 

tests/FSharp.Compiler.ComponentTests/Conformance/BasicGrammarElements/OperatorNames/BasicOperatorNames.fs

@@ -14,3 +14,5 @@ if !10 <> 3628800 then failwith "Failed: : 1"
 // Binary
 let (<<<) x y = x - x * y 
 if 10 <<< 3 <> -20 then failwith "Failed: : 2"
+
+let (>:) x y = x + x * y

tests/FSharp.Compiler.ComponentTests/Conformance/BasicGrammarElements/OperatorNames/OperatorNames.fs

@@ -73,4 +73,4 @@ module OperatorNames =
         |> asExe
         |> withOptions ["--warnaserror+"; "--nowarn:3370"; "--nowarn:988"]
         |> compileExeAndRun
-        |> shouldSucceed
+        |> shouldSucceed

tests/FSharp.Compiler.ComponentTests/ErrorMessages/ClassesTests.fs

@@ -686,4 +686,22 @@ type X =
         app
         |> withLangVersion80
         |> compile
+        |> shouldSucceed
+
+    [<Fact>]
+    let ``No separator between member and type annotation`` () =
+         FSharp """
+    type IFoo<'T> =
+        abstract member Bar<'T>: string -> unit
+            """
+        |> typecheck
+        |> shouldSucceed
+
+    [<Fact>]
+    let ``Separator between member and type annotation`` () =
+         FSharp """
+    type IFoo<'T> =
+        abstract member Bar<'T> : string -> unit
+            """
+        |> typecheck
         |> shouldSucceed