added variables and producer check

internal/parser/ast.go

@@ -125,3 +125,21 @@ type Pragma struct {
 }
 
 func (p *Pragma) Pos() Position { return p.Position }
+
+type VariableDefinition struct {
+	Position     Position
+	Name         string
+	TypeExpr     string
+	DefaultValue Value
+}
+
+func (v *VariableDefinition) Pos() Position { return v.Position }
+func (v *VariableDefinition) isDefinition() {}
+
+type VariableReferenceValue struct {
+	Position Position
+	Name     string
+}
+
+func (v *VariableReferenceValue) Pos() Position { return v.Position }
+func (v *VariableReferenceValue) isValue()      {}

internal/parser/lexer.go

@@ -23,6 +23,11 @@ const (
 	TokenComment
 	TokenDocstring
 	TokenComma
+	TokenColon
+	TokenPipe
+	TokenLBracket
+	TokenRBracket
+	TokenSymbol
 )
 
 type Token struct {
@@ -124,6 +129,16 @@ func (l *Lexer) NextToken() Token {
 			return l.emit(TokenRBrace)
 		case ',':
 			return l.emit(TokenComma)
+		case ':':
+			return l.emit(TokenColon)
+		case '|':
+			return l.emit(TokenPipe)
+		case '[':
+			return l.emit(TokenLBracket)
+		case ']':
+			return l.emit(TokenRBracket)
+		case '&', '?', '!', '<', '>', '*', '(', ')':
+			return l.emit(TokenSymbol)
 		case '"':
 			return l.lexString()
 		case '/':
@@ -151,7 +166,7 @@ func (l *Lexer) NextToken() Token {
 func (l *Lexer) lexIdentifier() Token {
 	for {
 		r := l.next()
-		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '-' || r == '.' || r == ':' {
+		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '-' || r == '.' {
 			continue
 		}
 		l.backup()
@@ -247,7 +262,7 @@ func (l *Lexer) lexHashIdentifier() Token {
 	// We are at '#', l.start is just before it
 	for {
 		r := l.next()
-		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '-' || r == '.' || r == ':' || r == '#' {
+		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '-' || r == '.' || r == '#' {
 			continue
 		}
 		l.backup()

internal/parser/parser.go

@@ -101,6 +101,9 @@ func (p *Parser) parseDefinition() (Definition, bool) {
 	switch tok.Type {
 	case TokenIdentifier:
 		name := tok.Value
+		if name == "#var" {
+			return p.parseVariableDefinition(tok)
+		}
 		if p.peek().Type != TokenEqual {
 			p.addError(tok.Position, "expected =")
 			return nil, false
@@ -244,6 +247,8 @@ func (p *Parser) parseValue() (Value, bool) {
 			true
 	case TokenIdentifier:
 		return &ReferenceValue{Position: tok.Position, Value: tok.Value}, true
+	case TokenObjectIdentifier:
+		return &VariableReferenceValue{Position: tok.Position, Name: tok.Value}, true
 	case TokenLBrace:
 		arr := &ArrayValue{Position: tok.Position}
 		for {
@@ -269,3 +274,53 @@ func (p *Parser) parseValue() (Value, bool) {
 		return nil, false
 	}
 }
+
+func (p *Parser) parseVariableDefinition(startTok Token) (Definition, bool) {
+	nameTok := p.next()
+	if nameTok.Type != TokenIdentifier {
+		p.addError(nameTok.Position, "expected variable name")
+		return nil, false
+	}
+
+	if p.next().Type != TokenColon {
+		p.addError(nameTok.Position, "expected :")
+		return nil, false
+	}
+
+	var typeTokens []Token
+	startLine := nameTok.Position.Line
+
+	for {
+		t := p.peek()
+		if t.Position.Line > startLine || t.Type == TokenEOF {
+			break
+		}
+		if t.Type == TokenEqual {
+			break
+		}
+		typeTokens = append(typeTokens, p.next())
+	}
+
+	typeExpr := ""
+	for _, t := range typeTokens {
+		typeExpr += t.Value + " "
+	}
+
+	var defVal Value
+	if p.peek().Type == TokenEqual {
+		p.next()
+		val, ok := p.parseValue()
+		if ok {
+			defVal = val
+		} else {
+			return nil, false
+		}
+	}
+
+	return &VariableDefinition{
+		Position:     startTok.Position,
+		Name:         nameTok.Value,
+		TypeExpr:     strings.TrimSpace(typeExpr),
+		DefaultValue: defVal,
+	}, true
+}