changed table types to support implementing 'let', also integrated stdlib into repl

ast/eval.go

@@ -34,7 +34,7 @@ func (t *Token) Eval(funcs FuncTable, vars VarTable) *Token {
 
         switch (t_.Tag) {
         case SYMBOL:
-            maybeToken := vars.GetVar(t_.Inner.(string))
+            maybeToken := GetVar(t_.Inner.(string), vars)
             if maybeToken != nil {
                 tok := maybeToken.Eval(funcs, vars)
                 if tok.Tag == LIST {
@@ -52,7 +52,7 @@ func (t *Token) Eval(funcs FuncTable, vars VarTable) *Token {
 
     ret := reduce(t)
     if ret.Tag == SYMBOL {
-        f := funcs.GetFunction(ret.Inner.(string))
+        f := GetFunction(ret.Inner.(string), funcs)
         if f == nil {
             if !eligibleForSystemCall {
                 log.Log(log.DEBUG,

ast/func_table.go

@@ -28,7 +28,7 @@ type Function struct {
     Args        int // TODO: Make this a list of expected types (TAGs)
 }
 
-type FuncTable map[string]*Function
+type FuncTable *map[string]*Function
 
 // TODO: Currently only checks arg list length
 func (f Function) ParseFunction(args *Token) bool {
@@ -64,8 +64,8 @@ func (f Function) CallFunction(args *Token, vt VarTable, ft FuncTable) *Token {
     return f.Function(args, vt, ft)
 }
 
-func (table FuncTable) GetFunction(arg string) *Function {
-    target, ok := table[arg]
+func GetFunction(arg string, table FuncTable) *Function {
+    target, ok := (*table)[arg]
     if !ok {
         log.Log(log.DEBUG,
                 "function " + arg + " not found",

ast/var_table.go

@@ -17,10 +17,10 @@
 
 package ast
 
-type VarTable map[string]*Token
+type VarTable *map[string]*Token
 
-func (vt VarTable) GetVar(arg string) *Token {
-    val, ok := vt[arg]
+func GetVar(arg string, vt VarTable) *Token {
+    val, ok := (*vt)[arg]
     if !ok {
         return nil
     }
@@ -30,11 +30,11 @@ func (vt VarTable) GetVar(arg string) *Token {
 
 // Library represents variables defined in inner scope
 // It is assumed library is ordered from innermost scope to outermost scope
-func GetVar(arg string, library []VarTable) *Token {
+func GetVarFromTables(arg string, library []VarTable) *Token {
     var res *Token
     res = nil
     for i := 0; i < len(library); i += 1 {
-        res = library[i].GetVar(arg)
+        res = GetVar(arg, library[i])
         if res != nil {
             // TODO: Log scope res was found in?
             break