Add support for very basic string implementation

bootstrap/pkg/ast/ast.go

@@ -34,6 +34,7 @@ const (
 	Fn
 	NativeFn
 	Namespace
+	String
 	Block // Dont' mistake it with block from other programming languages
 
 )

bootstrap/pkg/core/eval.go

@@ -36,6 +36,9 @@ func evalForm(rt *Runtime, scope IScope, form IExpr) (IExpr, IError) {
 	case ast.Number:
 		return form, nil
 
+	case ast.String:
+		return form, nil
+
 	// Symbol evaluation rules:
 	// * If it's a NS qualified symbol (NSQS), Look it up in the external symbol table of
 	// the current namespace.

bootstrap/pkg/core/parser.go

@@ -208,8 +208,24 @@ func readRawSymbol(parser IParsable) (IExpr, IError) {
 
 	return sym, nil
 }
+func readString(parser IParsable) (IExpr, IError) {
+	str := ""
 
-// readNumber reads a number with respect to its sign and whether it's
+	for {
+		c := parser.next(false)
+		if c == nil {
+			return nil, makeErrorAtPoint(parser, "reached end of file while scanning a string")
+		}
+
+		if *c == "\"" {
+			node := MakeNode(parser.Buffer(), parser.GetLocation()-len(str), parser.GetLocation())
+			return MakeString(node, str), nil
+		}
+		str = str + *c
+	}
+}
+
+// readNumber reads a number with respect to its sign and whether it's, a ...interface{}
 // a decimal or a float
 func readNumber(parser IParsable, neg bool) (IExpr, IError) {
 	isDouble := false
@@ -267,9 +283,10 @@ func readSymbol(parser IParsable) (IExpr, IError) {
 		return nil, makeErrorAtPoint(parser, "unexpected end of file while scanning a symbol")
 	}
 
-	// if c == "\"" {
-	// 	return readString(parser)
-	// }
+	if *c == "\"" {
+		parser.next(false)
+		return readString(parser)
+	}
 
 	// Weird, But go won't stop complaining without this swap
 	char := *c

bootstrap/pkg/core/string.go

@@ -0,0 +1,46 @@
+/*
+ Serene --- Yet an other Lisp
+
+Copyright (c) 2020  Sameer Rahmani <lxsameer@gnu.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package core
+
+import (
+	"fmt"
+
+	"serene-lang.org/bootstrap/pkg/ast"
+)
+
+type String struct {
+	Node
+	content string
+}
+
+func (s *String) GetType() ast.NodeType {
+	return ast.String
+}
+
+func (s *String) String() string {
+	return s.content
+}
+
+func (s *String) ToDebugStr() string {
+	return fmt.Sprintf("<%s at %p>", s.content, s)
+}
+
+func MakeString(n Node, s string) *String {
+	return &String{n, s}
+}