func builtinQuoted2List(context *runtime.FunctionCallContext) (*runtime.Value, error) {
if err := runtime.ValidateArguments(context, runtime.QuotedValue); err != nil {
return nil, err
}
quoted := context.Args[0].Quoted
if list, isList := quoted.(*parser.ListNode); isList {
l := runtime.NewListValue()
for _, listNode := range list.Nodes {
l.List = append(l.List, runtime.NewQuotedValue(listNode))
}
return l, nil
} else {
return nil, runtime.NewRuntimeError(context.Pos, "expected a quoted list, not %s", quoted.Name())
}
}
func builtinDefmacro(context *runtime.MacroCallContext) (*runtime.Value, error) {
name := context.Nodes[0].(*parser.IdentifierNode).Token.Data
if name == "_" {
return nil, runtime.NewRuntimeError(context.Nodes[0].Pos(), "disallowed macro name")
}
if context.Block.Scope.GetSymbol(name) != nil && context.Block.Scope.GetSymbol(name).Const {
return nil, runtime.NewRuntimeError(context.Nodes[0].Pos(), "%s is a constant and cannot be modified", name)
}
argNodes := context.Nodes[1].(*parser.ListNode)
var args []string
callback := context.Nodes[2].(*parser.ListNode)
if len(callback.Nodes) == 0 {
return nil, runtime.NewRuntimeError(callback.Pos(), "empty macro body")
}
for _, argNode := range argNodes.Nodes {
ident, ok := argNode.(*parser.IdentifierNode)
if !ok {
return nil, runtime.NewRuntimeError(argNode.Pos(), "expected an identifier")
}
args = append(args, ident.Token.Data)
}
macro := runtime.NewMacro(func(handlerContext *runtime.MacroCallContext) (*runtime.Value, error) {
block := runtime.NewBlock([]parser.Node{callback}, runtime.NewScope(handlerContext.Block.Scope))
for i, arg := range args {
block.Scope.SetSymbolLocally(arg, runtime.NewSymbol(runtime.NewQuotedValue(handlerContext.Nodes[i])))
}
return block.Eval()
}, false)
context.Block.Scope.SetMacro(name, macro)
return runtime.Nil, nil
}