private void Run(ProgramNode program, EbiScope scope)
{
foreach (var(node, i) in program.Nodes.Select((node, i) => (node, i)))
{
Evaluate(scope, node);
}
}
public void Run(ProgramNode program)
{
if (!configuration.PersistContext)
{
globalScope = EbiScope.CreateGlobalScope();
}
Run(program, globalScope);
}
private EbiValueBase Evaluate(EbiScope scope, ExpressionNode expr)
{
return(expr switch
{
LiteralNode l => l.Value,
IdentifierNode id => scope[id.Name]?.Value ?? throw new RuntimeException($"No such identifier named '{id.Name}'"),
CallExpressionNode call => Evaluate(scope, call),
UnaryExpressionNode un => Evaluate(scope, un),
BinaryExpressionNode bin => Evaluate(scope, bin),
_ => new EbiNull(),
});
private void Evaluate(EbiScope scope, StatementNode statement)
{
switch (statement)
{
case ExpressionStatementNode expr:
Evaluate(scope, expr.Expression);
break;
case BlockStatementNode block:
Run(block.Statements, new EbiScope(scope));
break;
case RepeatStatementNode repeat:
try
{
while (true)
{
Evaluate(scope, repeat.Statement);
}
}
catch (BreakException) { }
catch (ContinueException)
{
// TODO: ここだけじゃないけど、現在の実装だとあっという間にstackoverflowになってしまうので実装法を考え直したい
Evaluate(scope, repeat);
}
break;
case BreakStatementNode:
throw new BreakException();
case ContinueStatementNode:
throw new ContinueException();
}
;
}
