/// <summary>
/// Gets an <see cref="OpenLispSymbol"/> from <see cref="Env"/>.
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public OpenLispVal Get(OpenLispSymbol key)
{
Env e = Find(key);
if (e == null)
{
throw new OpenLispException("'" + key.Value + "' not found");
}
return(e._data[key.Value]);
}
/// <summary>
/// Expands a macro.
///
/// TODO: refactor to move to <see cref="OpenLisp.Core.StaticClasses.CoreNameSpace"/>.
/// </summary>
/// <param name="abstractSyntaxTree"></param>
/// <param name="environment"></param>
/// <returns></returns>
public static OpenLispVal MacroExpand(OpenLispVal abstractSyntaxTree, Env environment)
{
while (IsMacroCall(abstractSyntaxTree, environment))
{
OpenLispSymbol caputPrimus = (OpenLispSymbol)((OpenLispList)abstractSyntaxTree)[0];
OpenLispFunc macro = (OpenLispFunc)environment.Get(caputPrimus);
abstractSyntaxTree = macro.Apply(((OpenLispList)abstractSyntaxTree).Rest());
}
return(abstractSyntaxTree);
}
/// <summary>
/// Sets an <see cref="OpenLispSymbol"/> key's value to an instance of <see cref="OpenLispVal"/>.
/// </summary>
/// <param name="key"></param>
/// <param name="value"></param>
/// <returns></returns>
public Env Set(OpenLispSymbol key, OpenLispVal value)
{
_data[key.Value] = value;
return(this);
}
/// <summary>
/// Finds an <see cref="OpenLispSymbol"/> in <see cref="Env._data"/>.
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public Env Find(OpenLispSymbol key)
{
return(_data.ContainsKey(key.Value) ? this : _outer?.Find(key));
}