private Ast.Stmt ParseIfStmt(TokenQueue q)
{
var stmt = new Ast.IfStmt {
SourceToken = q.SourceToken
};
q.Take("if");
stmt.Condition = ParseExpr(q);
stmt.Block = ParseBlock(q);
if (q.Peek() == "else")
{
q.Take("else");
stmt.ElseBlock = ParseBlock(q);
}
return(stmt);
}
private void ExecuteIfStmt(Ast.IfStmt stmt, ScriptEnv env)
{
var condition = EvaluateExpr <long>(stmt.Condition, env);
if (condition == 0)
{
if (stmt.ElseBlock != null)
{
ExecuteBlock(stmt.ElseBlock, env);
}
}
else if (condition == 1)
{
ExecuteBlock(stmt.Block, env);
}
else
{
throw new ScriptException(
$"Evaluation of IF condition expression \"{stmt.Condition.Sql}\" " +
$"produced a value of {condition} instead of the expected 0 or 1.");
}
}