All: add keywords.

Also, fix nth and count to match cloure.

13 files changed, 106 insertions, 78 deletions

diff --git a/vb/core.vb b/vb/core.vb
index 43fc30f..771d0cc 100644
--- a/vb/core.vb
+++ b/vb/core.vb
@@ -69,6 +69,24 @@ Namespace Mal
             End If
         End Function
 
+        Shared Function keyword(a As MalList) As MalVal
+            Dim s As String = DirectCast(a(0),MalString).getValue()
+            return new MalString(ChrW(&H029e) & s)
+        End Function
+
+        Shared Function keyword_Q(a As MalList) As MalVal
+            If TypeOf a(0) Is MalString Then
+                Dim s As String = DirectCast(a(0),MalString).getValue()
+                If s.Substring(0,1) = Strings.ChrW(&H029e) Then
+                    return MalTrue
+                Else
+                    return MalFalse
+                End If
+            Else
+                return MalFalse
+            End If
+        End Function
+
 
         ' Number functions
         Shared Function lt(a As MalList) As MalVal
@@ -258,7 +276,13 @@ Namespace Mal
         End Function
 
         Shared Function nth(a As MalList) As MalVal
-            return DirectCast(a(0),MalList)( DirectCast(a(1),MalInt).getValue() )
+            Dim idx As Integer = DirectCast(a(1),MalInt).getValue()
+            If (idx < DirectCast(a(0),MalList).size()) Then
+                return DirectCast(a(0),MalList)( idx )
+            Else
+                throw new Mal.types.MalException(
+                    "nth: index out of range")
+            End If
         End Function
 
         Shared Function first(a As MalList) As MalVal
@@ -278,7 +302,11 @@ Namespace Mal
         End Function
 
         Shared Function count(a As MalList) As MalVal
-            return new MalInt(DirectCast(a(0),MalList).size())
+            If a(0) Is Nil Then
+                return new MalInt(0)
+            Else
+                return new MalInt(DirectCast(a(0),MalList).size())
+            End If
         End Function
 
         Shared Function conj(a As MalList) As MalVal
@@ -371,6 +399,8 @@ Namespace Mal
             ns.Add("false?", New MalFunc(AddressOf false_Q))
             ns.Add("symbol", new MalFunc(AddressOf symbol))
             ns.Add("symbol?", New MalFunc(AddressOf symbol_Q))
+            ns.Add("keyword", new MalFunc(AddressOf keyword))
+            ns.Add("keyword?", New MalFunc(AddressOf keyword_Q))
 
             ns.Add("pr-str",New MalFunc(AddressOf pr_str))
             ns.Add("str", New MalFunc(AddressOf str))
diff --git a/vb/env.vb b/vb/env.vb
index 3095344..a2c4628 100644
--- a/vb/env.vb
+++ b/vb/env.vb
@@ -26,8 +26,8 @@ Namespace Mal
                 Next
             End Sub
             
-            Public Function find(key As String) As Env
-                If data.ContainsKey(key) Then
+            Public Function find(key As MalSymbol) As Env
+                If data.ContainsKey(key.getName()) Then
                     return Me
                 Else If outer IsNot Nothing Then
                     return outer.find(key)
@@ -36,18 +36,18 @@ Namespace Mal
                 End If
             End Function
 
-            Public Function do_get(key As String) As MalVal
+            Public Function do_get(key As MalSymbol) As MalVal
                 Dim e As Env = find(key)
                 If e Is Nothing Then
                     throw New Mal.types.MalException(
-                            "'" & key & "' not found")
+                            "'" & key.getName() & "' not found")
                 Else
-                    return e.data(key)
+                    return e.data(key.getName())
                 End If
             End Function
 
-            Public Function do_set(key As String, value As MalVal) As Env
-                data(key) = value
+            Public Function do_set(key As MalSymbol, value As MalVal) As Env
+                data(key.getName()) = value
                 return Me
             End Function
         End Class
diff --git a/vb/printer.vb b/vb/printer.vb
index 212b89c..3f3e6e2 100644
--- a/vb/printer.vb
+++ b/vb/printer.vb
@@ -22,7 +22,9 @@ Namespace Mal
                              print_readably As Boolean) As String
             Dim strs As New List(Of String)
             For Each entry As KeyValuePair(Of String, MalVal) In value
-                If print_readably Then
+                If entry.Key.Length > 0 and entry.Key(0) = ChrW(&H029e) Then
+                    strs.Add(":" & entry.Key.Substring(1))
+                Else If print_readably Then
                     strs.Add("""" & entry.Key.ToString() & """")
                 Else
                     strs.Add(entry.Key.ToString())
diff --git a/vb/reader.vb b/vb/reader.vb
index 121aac2..9d4e03d 100644
--- a/vb/reader.vb
+++ b/vb/reader.vb
@@ -64,7 +64,7 @@ Namespace Mal
 
         Shared Function read_atom(rdr As Reader) As MalVal
             Dim token As String = rdr.get_next()
-            Dim pattern As String = "(^-?[0-9]+$)|(^-?[0-9][0-9.]*$)|(^nil$)|(^true$)|(^false$)|^("".*"")$|(^[^""]*$)"
+            Dim pattern As String = "(^-?[0-9]+$)|(^-?[0-9][0-9.]*$)|(^nil$)|(^true$)|(^false$)|^("".*"")$|^:(.*)|(^[^""]*$)"
             Dim regex As Regex = New Regex(pattern)
             Dim match As Match = regex.Match(token)
             'Console.WriteLine("token: ^" + token + "$")
@@ -86,7 +86,9 @@ Namespace Mal
                         .Replace("\""", """") _
                         .Replace("\n", Environment.NewLine))
             Else If match.Groups(7).Value <> String.Empty Then
-                return New Mal.types.MalSymbol(match.Groups(7).Value)
+                return New Mal.types.MalString(ChrW(&H029e) & match.Groups(7).Value)
+            Else If match.Groups(8).Value <> String.Empty Then
+                return New Mal.types.MalSymbol(match.Groups(8).Value)
             Else
                 throw New ParseError("unrecognized '" & match.Groups(0).Value & "'")
             End If
diff --git a/vb/step3_env.vb b/vb/step3_env.vb
index 5793fdb..dfee614 100644
--- a/vb/step3_env.vb
+++ b/vb/step3_env.vb
@@ -21,8 +21,7 @@ Namespace Mal
         ' eval
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -66,7 +65,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -77,7 +76,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 return EVAL(a2, let_env)
             Case Else
@@ -119,10 +118,10 @@ Namespace Mal
             Dim args As String() = Environment.GetCommandLineArgs()
 
             repl_env = New MalEnv(Nothing)
-            repl_env.do_set("+", New MalFunc(AddressOf add))
-            repl_env.do_set("-", New MalFunc(AddressOf minus))
-            repl_env.do_set("*", New MalFunc(AddressOf mult))
-            repl_env.do_set("/", New MalFunc(AddressOf div))
+            repl_env.do_set(new MalSymbol("+"), New MalFunc(AddressOf add))
+            repl_env.do_set(new MalSymbol("-"), New MalFunc(AddressOf minus))
+            repl_env.do_set(new MalSymbol("*"), New MalFunc(AddressOf mult))
+            repl_env.do_set(new MalSymbol("/"), New MalFunc(AddressOf div))
 
 
             If args.Length > 1 AndAlso args(1) = "--raw" Then
diff --git a/vb/step4_if_fn_do.vb b/vb/step4_if_fn_do.vb
index 4cf8721..470ae86 100644
--- a/vb/step4_if_fn_do.vb
+++ b/vb/step4_if_fn_do.vb
@@ -21,8 +21,7 @@ Namespace Mal
         ' eval
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -83,7 +82,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -94,7 +93,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 return EVAL(a2, let_env)
             Case "do"
@@ -152,7 +151,7 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
 
             ' core.mal: defined using the language itself
diff --git a/vb/step5_tco.vb b/vb/step5_tco.vb
index 3c1f51c..bb36b22 100644
--- a/vb/step5_tco.vb
+++ b/vb/step5_tco.vb
@@ -21,8 +21,7 @@ Namespace Mal
         ' eval
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -85,7 +84,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -96,7 +95,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -161,7 +160,7 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
 
             ' core.mal: defined using the language itself
diff --git a/vb/step6_file.vb b/vb/step6_file.vb
index 58f8cd2..9ea0e9f 100644
--- a/vb/step6_file.vb
+++ b/vb/step6_file.vb
@@ -22,8 +22,7 @@ Namespace Mal
         ' eval
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -86,7 +85,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -97,7 +96,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -166,9 +165,9 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
-            repl_env.do_set("eval", new MalFunc(AddressOf do_eval))
+            repl_env.do_set(new MalSymbol("eval"), new MalFunc(AddressOf do_eval))
             Dim fileIdx As Integer = 1
             If args.Length > 1 AndAlso args(1) = "--raw" Then
                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
@@ -178,7 +177,7 @@ Namespace Mal
             For i As Integer = fileIdx+1 To args.Length-1
                 argv.conj_BANG(new MalString(args(i)))
             Next
-            repl_env.do_set("*ARGV*", argv)
+            repl_env.do_set(new MalSymbol("*ARGV*"), argv)
 
             ' core.mal: defined using the language itself
             REP("(def! not (fn* (a) (if a false true)))")
diff --git a/vb/step7_quote.vb b/vb/step7_quote.vb
index 3f2d614..f38741e 100644
--- a/vb/step7_quote.vb
+++ b/vb/step7_quote.vb
@@ -51,8 +51,7 @@ Namespace Mal
 
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -115,7 +114,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -126,7 +125,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -199,9 +198,9 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
-            repl_env.do_set("eval", new MalFunc(AddressOf do_eval))
+            repl_env.do_set(new MalSymbol("eval"), new MalFunc(AddressOf do_eval))
             Dim fileIdx As Integer = 1
             If args.Length > 1 AndAlso args(1) = "--raw" Then
                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
@@ -211,7 +210,7 @@ Namespace Mal
             For i As Integer = fileIdx+1 To args.Length-1
                 argv.conj_BANG(new MalString(args(i)))
             Next
-            repl_env.do_set("*ARGV*", argv)
+            repl_env.do_set(new MalSymbol("*ARGV*"), argv)
 
             ' core.mal: defined using the language itself
             REP("(def! not (fn* (a) (if a false true)))")
diff --git a/vb/step8_macros.vb b/vb/step8_macros.vb
index 1a7f211..400dbe7 100644
--- a/vb/step8_macros.vb
+++ b/vb/step8_macros.vb
@@ -52,8 +52,8 @@ Namespace Mal
             If TypeOf ast Is MalList Then
                 Dim a0 As MalVal = DirectCast(ast,MalList)(0)
                 If TypeOf a0 Is MalSymbol AndAlso _
-                    env.find(DirectCast(a0,MalSymbol).getName()) IsNot Nothing Then
-                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol).getName())
+                    env.find(DirectCast(a0,MalSymbol)) IsNot Nothing Then
+                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol))
                     If TypeOf mac Is MalFunc AndAlso _
                         DirectCast(mac,MalFunc).isMacro() Then
                         return True
@@ -66,7 +66,7 @@ Namespace Mal
         Shared Function macroexpand(ast As MalVal, env As MalEnv) As MalVal
             While is_macro_call(ast, env)
                 Dim a0 As MalSymbol = DirectCast(DirectCast(ast,MalList)(0),MalSymbol)
-                Dim mac As MalFunc = DirectCast(env.do_get(a0.getName()),MalFunc)
+                Dim mac As MalFunc = DirectCast(env.do_get(a0),MalFunc)
                 ast = mac.apply(DirectCast(ast,MalList).rest())
             End While
             return ast
@@ -74,8 +74,7 @@ Namespace Mal
 
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -143,7 +142,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -154,7 +153,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -167,7 +166,7 @@ Namespace Mal
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
                 DirectCast(res,MalFunc).setMacro()
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "macroexpand"
                 Dim a1 As MalVal = ast(1)
@@ -237,9 +236,9 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
-            repl_env.do_set("eval", new MalFunc(AddressOf do_eval))
+            repl_env.do_set(new MalSymbol("eval"), new MalFunc(AddressOf do_eval))
             Dim fileIdx As Integer = 1
             If args.Length > 1 AndAlso args(1) = "--raw" Then
                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
@@ -249,7 +248,7 @@ Namespace Mal
             For i As Integer = fileIdx+1 To args.Length-1
                 argv.conj_BANG(new MalString(args(i)))
             Next
-            repl_env.do_set("*ARGV*", argv)
+            repl_env.do_set(new MalSymbol("*ARGV*"), argv)
 
             ' core.mal: defined using the language itself
             REP("(def! not (fn* (a) (if a false true)))")
diff --git a/vb/step9_try.vb b/vb/step9_try.vb
index 5bf600d..d4a7af4 100644
--- a/vb/step9_try.vb
+++ b/vb/step9_try.vb
@@ -52,8 +52,8 @@ Namespace Mal
             If TypeOf ast Is MalList Then
                 Dim a0 As MalVal = DirectCast(ast,MalList)(0)
                 If TypeOf a0 Is MalSymbol AndAlso _
-                    env.find(DirectCast(a0,MalSymbol).getName()) IsNot Nothing Then
-                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol).getName())
+                    env.find(DirectCast(a0,MalSymbol)) IsNot Nothing Then
+                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol))
                     If TypeOf mac Is MalFunc AndAlso _
                         DirectCast(mac,MalFunc).isMacro() Then
                         return True
@@ -66,7 +66,7 @@ Namespace Mal
         Shared Function macroexpand(ast As MalVal, env As MalEnv) As MalVal
             While is_macro_call(ast, env)
                 Dim a0 As MalSymbol = DirectCast(DirectCast(ast,MalList)(0),MalSymbol)
-                Dim mac As MalFunc = DirectCast(env.do_get(a0.getName()),MalFunc)
+                Dim mac As MalFunc = DirectCast(env.do_get(a0),MalFunc)
                 ast = mac.apply(DirectCast(ast,MalList).rest())
             End While
             return ast
@@ -74,8 +74,7 @@ Namespace Mal
 
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -143,7 +142,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -154,7 +153,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -167,7 +166,7 @@ Namespace Mal
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
                 DirectCast(res,MalFunc).setMacro()
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "macroexpand"
                 Dim a1 As MalVal = ast(1)
@@ -260,9 +259,9 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
-            repl_env.do_set("eval", new MalFunc(AddressOf do_eval))
+            repl_env.do_set(new MalSymbol("eval"), new MalFunc(AddressOf do_eval))
             Dim fileIdx As Integer = 1
             If args.Length > 1 AndAlso args(1) = "--raw" Then
                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
@@ -272,7 +271,7 @@ Namespace Mal
             For i As Integer = fileIdx+1 To args.Length-1
                 argv.conj_BANG(new MalString(args(i)))
             Next
-            repl_env.do_set("*ARGV*", argv)
+            repl_env.do_set(new MalSymbol("*ARGV*"), argv)
 
             ' core.mal: defined using the language itself
             REP("(def! not (fn* (a) (if a false true)))")
diff --git a/vb/stepA_interop.vb b/vb/stepA_interop.vb
index 01702fa..f9af038 100644
--- a/vb/stepA_interop.vb
+++ b/vb/stepA_interop.vb
@@ -52,8 +52,8 @@ Namespace Mal
             If TypeOf ast Is MalList Then
                 Dim a0 As MalVal = DirectCast(ast,MalList)(0)
                 If TypeOf a0 Is MalSymbol AndAlso _
-                    env.find(DirectCast(a0,MalSymbol).getName()) IsNot Nothing Then
-                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol).getName())
+                    env.find(DirectCast(a0,MalSymbol)) IsNot Nothing Then
+                    Dim mac As MalVal = env.do_get(DirectCast(a0,MalSymbol))
                     If TypeOf mac Is MalFunc AndAlso _
                         DirectCast(mac,MalFunc).isMacro() Then
                         return True
@@ -66,7 +66,7 @@ Namespace Mal
         Shared Function macroexpand(ast As MalVal, env As MalEnv) As MalVal
             While is_macro_call(ast, env)
                 Dim a0 As MalSymbol = DirectCast(DirectCast(ast,MalList)(0),MalSymbol)
-                Dim mac As MalFunc = DirectCast(env.do_get(a0.getName()),MalFunc)
+                Dim mac As MalFunc = DirectCast(env.do_get(a0),MalFunc)
                 ast = mac.apply(DirectCast(ast,MalList).rest())
             End While
             return ast
@@ -74,8 +74,7 @@ Namespace Mal
 
         Shared Function eval_ast(ast As MalVal, env As MalEnv) As MalVal
             If TypeOf ast Is MalSymbol Then
-                Dim sym As MalSymbol = DirectCast(ast, MalSymbol)
-                return env.do_get(sym.getName())
+                return env.do_get(DirectCast(ast, MalSymbol))
             Else If TypeOf ast Is MalList Then
                 Dim old_lst As MalList = DirectCast(ast, MalList)
                 Dim new_lst As MalList
@@ -143,7 +142,7 @@ Namespace Mal
                 Dim a1 As MalVal = ast(1)
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "let*"
                 Dim a1 As MalVal = ast(1)
@@ -154,7 +153,7 @@ Namespace Mal
                 For i As Integer = 0 To (DirectCast(a1,MalList)).size()-1 Step 2
                     key = DirectCast(DirectCast(a1,MalList)(i),MalSymbol)
                     val = DirectCast(a1,MalList)(i+1)
-                    let_env.do_set(key.getName(), EVAL(val, let_env))
+                    let_env.do_set(key, EVAL(val, let_env))
                 Next
                 orig_ast = a2
                 env = let_env
@@ -167,7 +166,7 @@ Namespace Mal
                 Dim a2 As MalVal = ast(2)
                 Dim res As MalVal = EVAL(a2, env)
                 DirectCast(res,MalFunc).setMacro()
-                env.do_set(DirectCast(a1,MalSymbol).getName(), res)
+                env.do_set(DirectCast(a1,MalSymbol), res)
                 return res
             Case "macroexpand"
                 Dim a1 As MalVal = ast(1)
@@ -260,9 +259,9 @@ Namespace Mal
 
             ' core.vb: defined using VB.NET
             For Each entry As KeyValuePair(Of String,MalVal) In core.ns()
-                repl_env.do_set(entry.Key, entry.Value)
+                repl_env.do_set(new MalSymbol(entry.Key), entry.Value)
             Next
-            repl_env.do_set("eval", new MalFunc(AddressOf do_eval))
+            repl_env.do_set(new MalSymbol("eval"), new MalFunc(AddressOf do_eval))
             Dim fileIdx As Integer = 1
             If args.Length > 1 AndAlso args(1) = "--raw" Then
                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
@@ -272,7 +271,7 @@ Namespace Mal
             For i As Integer = fileIdx+1 To args.Length-1
                 argv.conj_BANG(new MalString(args(i)))
             Next
-            repl_env.do_set("*ARGV*", argv)
+            repl_env.do_set(new MalSymbol("*ARGV*"), argv)
 
             ' core.mal: defined using the language itself
             REP("(def! *host-language* ""VB.NET"")")
diff --git a/vb/types.vb b/vb/types.vb
index 303a02e..4da75bd 100644
--- a/vb/types.vb
+++ b/vb/types.vb
@@ -232,7 +232,9 @@ namespace Mal
                 return """" & value & """"
             End Function
             Public Overrides Function ToString(print_readably As Boolean) As String
-                If print_readably Then
+                If value.Length > 0 AndAlso value(0) = ChrW(&H029e) Then
+                    return ":" & value.Substring(1)
+                Else If print_readably Then
                     return """" & _
                            value.Replace("\", "\\") _
                                 .Replace("""", "\""") _