Add support for maps and arrays

ast/ast.go

@@ -64,6 +64,24 @@ type Value struct {
 	Not bool
 }
 
+type Map struct {
+	Map      map[Node]Node
+	Position Position
+}
+
+func (m Map) Pos() Position {
+	return m.Position
+}
+
+type Array struct {
+	Array    []Node
+	Position Position
+}
+
+func (a Array) Pos() Position {
+	return a.Position
+}
+
 type Expr struct {
 	First    Node
 	Operator Operator

parser/salix.peg

@@ -116,13 +116,49 @@ ParamList = '(' params:(Expr ( ',' _ Expr )* )? ')' {
     return out, nil
 }
 
-Value = not:"!"? node:(MethodCall / FieldAccess / Index / String / RawString / Float / Integer / Bool / FuncCall / VariableOr / Ident / ParenExpr) {
+Value = not:"!"? node:(MethodCall / FieldAccess / Index / String / RawString / Float / Integer / Bool / FuncCall / VariableOr / Ident / ParenExpr / Array / Map) {
     return ast.Value{
         Node: node.(ast.Node),
         Not:  not != nil,
     }, nil
 }
 
+Map = '{' _ fpair:(Assignable _ ':' _ Assignable)? _ pairs:(',' _ Assignable _ ':' _ Assignable _)* _ ','? _ '}' {
+    out := ast.Map{
+        Map: map[ast.Node]ast.Node{},
+        Position: getPos(c),
+    }
+
+    fpairSlice := toAnySlice(fpair)
+    if fpairSlice == nil {
+        return out, nil
+    } else {
+        out.Map[fpairSlice[0].(ast.Node)] = fpairSlice[4].(ast.Node)
+        for _, pair := range toAnySlice(pairs) {
+            pairSlice := toAnySlice(pair)
+            out.Map[pairSlice[2].(ast.Node)] = pairSlice[6].(ast.Node)
+        }
+    }
+
+    return out, nil
+}
+
+Array = '[' _ fval:Assignable? _ vals:(',' _ Assignable _)* ','? _ ']' {
+    out := ast.Array{Position: getPos(c)}
+
+    if fval == nil {
+        return out, nil
+    } else {
+        out.Array = append(out.Array, fval.(ast.Node))
+        for _, val := range toAnySlice(vals) {
+            valSlice := toAnySlice(val)
+            out.Array = append(out.Array, valSlice[2].(ast.Node))
+        }
+    }
+
+    return out, nil
+}
+
 VariableOr = variable:Ident _ '|' _ or:Assignable {
     return ast.VariableOr{
         Variable: variable.(ast.Ident),

salix.go

@@ -222,6 +222,10 @@ func (t *Template) getValue(node ast.Node, local map[string]any) (any, error) {
 		return t.evalTernary(node, local)
 	case ast.VariableOr:
 		return t.evalVariableOr(node, local)
+	case ast.Map:
+		return t.convertMap(node, local)
+	case ast.Array:
+		return t.convertArray(node, local)
 	case ast.Assignment:
 		return node, t.handleAssignment(node, local)
 	default:
@@ -290,6 +294,23 @@ func valueToString(node ast.Node) string {
 		} else {
 			return "#" + node.Name.Value + "()"
 		}
+	case ast.Map:
+		k, v := getOneMapPair(node)
+		if len(node.Map) > 1 {
+			return "{" + valueToString(k) + ": " + valueToString(v) + ", ...}"
+		} else if len(node.Map) == 1 {
+			return "{" + valueToString(k) + ": " + valueToString(v) + "}"
+		} else {
+			return "{}"
+		}
+	case ast.Array:
+		if len(node.Array) > 1 {
+			return "[" + valueToString(node.Array[0]) + ", ...]"
+		} else if len(node.Array) == 1 {
+			return "[" + valueToString(node.Array[0]) + "]"
+		} else {
+			return "[]"
+		}
 	case ast.EndTag:
 		return "#!" + node.Name.Value
 	case ast.ExprTag:
@@ -299,6 +320,13 @@ func valueToString(node ast.Node) string {
 	}
 }
 
+func getOneMapPair(m ast.Map) (k, v ast.Node) {
+	for key, val := range m.Map {
+		return key, val
+	}
+	return nil, nil
+}
+
 // unwrapASTValue unwraps an ast.Value node into its underlying value
 func (t *Template) unwrapASTValue(node ast.Value, local map[string]any) (any, error) {
 	v, err := t.getValue(node.Node, local)
@@ -317,6 +345,40 @@ func (t *Template) unwrapASTValue(node ast.Value, local map[string]any) (any, er
 	return v, err
 }
 
+// convertMap converts an ast.Map value into a map[any]any by recursively calling
+// getValue on each of its keys and values.
+func (t *Template) convertMap(node ast.Map, local map[string]any) (any, error) {
+	out := make(map[any]any, len(node.Map))
+	for keyNode, valNode := range node.Map {
+		key, err := t.getValue(keyNode, local)
+		if err != nil {
+			return nil, err
+		}
+
+		val, err := t.getValue(valNode, local)
+		if err != nil {
+			return nil, err
+		}
+
+		out[key] = val
+	}
+	return out, nil
+}
+
+// convertArray converts an ast.Array into an []any by recursively calling getValue
+// on each of its elements.
+func (t *Template) convertArray(node ast.Array, local map[string]any) (any, error) {
+	out := make([]any, len(node.Array))
+	for i, valNode := range node.Array {
+		val, err := t.getValue(valNode, local)
+		if err != nil {
+			return nil, err
+		}
+		out[i] = val
+	}
+	return out, nil
+}
+
 // getVar tries to get a variable from the local map. If it's not found,
 // it'll try the global variable map. If it doesn't exist in either map,
 // it will return an error.