much stdlib docs

stdlib/arith.go

@@ -29,7 +29,13 @@ import (
 // perhaps we simply write out arithmetic routines that operate on the strings
 // then we need not worry about storage length.
 
-func num_cast(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+/* Takes 1 argument (must be a string)
+ * will attempt to cast it to a number.
+ * will return nil if cast fails
+ *
+ * Example: (number "3.4")
+ */
+func NumCast(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
     in = in.Eval(f, a, false)
     if in.Tag != ast.STRING {
         log.Log(log.ERR,
@@ -50,7 +56,7 @@ func num_cast(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
     return out
 }
 
-func add(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+func Add(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
     var res float64
 
     in = in.Eval(f, a, false)