The REPL no longer shows the last pop value if an error occurs

src/japl.nim

@@ -52,6 +52,7 @@ proc repl(vmObj: Option[VM]) =
     var source = ""
     let lineEditor = getLineEditor()
     var keep = true
+    var result: InterpretResult
     lineEditor.bindEvent(jeQuit):
         keep = false
     while keep:
@@ -64,8 +65,8 @@ proc repl(vmObj: Option[VM]) =
             echo "Goodbye!"
             break
         elif source != "":
-            discard bytecodeVM.interpret(source, "stdin")
-            if not bytecodeVM.lastPop.isJaplNil():
+            result = bytecodeVM.interpret(source, "stdin")
+            if not bytecodeVM.lastPop.isJaplNil() and result notin {CompileError, RuntimeError}:
                 echo stringify(bytecodeVM.lastPop)
                 bytecodeVM.lastPop = cast[ptr Nil](bytecodeVM.cached[2])
     bytecodeVM.freeVM()

src/types/closure.nim

@@ -1,63 +0,0 @@
-# Copyright 2020 Mattia Giambirtone
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-## Implements closures
-
-import baseObject
-import function
-import ../memory
-
-
-type Closure* = object of Obj
-    ## Represents a function
-    ## closing over values outside
-    ## of its lexical scope
-    function*: ptr Function
-
-
-proc newClosure(function: ptr Function): ptr Closure =
-    ## Initializes a new closure from a function
-    ## object
-    result = allocateObject(Closure, ObjectType.Closure)
-    result.function = function
-
-
-proc typeName*(self: ptr Closure): string =
-    result = "function"
-
-
-proc stringify*(self: ptr Closure): string =
-    if self.function.name != nil:
-        if self.function.name.toStr() == "<lambda function>":
-            result = self.function.name.toStr()
-        else:
-            result = "<function '" & self.function.name.toStr() & "'>"
-    else:
-        result = "<code object>"
-
-
-proc isFalsey*(self: ptr Closure): bool =
-    result = false
-
-
-proc hash*(self: ptr Closure): uint64 =
-    result = uint64(393027534)   # Arbitrary hash because ¯\_(ツ)_/¯
-
-
-proc eq*(self, other: ptr Closure): bool =
-    result = self.function == other.function  # Pointer equality
-
-
-proc eq*(self: ptr Closure, other: ptr Function): bool =
-    result = self.function == other

src/types/function.nim

@@ -1,17 +1,3 @@
-# Copyright 2020 Mattia Giambirtone
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
 import baseObject
 import ../meta/opcode
 import japlString

src/vm.nim

@@ -46,7 +46,7 @@ when DEBUG_TRACE_VM:
 type
     KeyboardInterrupt* = object of CatchableError
     ## Custom exception to handle Ctrl+C
-    InterpretResult = enum
+    InterpretResult* = enum
         ## All possible interpretation results
         Ok,
         CompileError,