private IObject EvalHashLiteral(HashLiteral hl, Environment env)
{
var pairs = new Dictionary <int, HashPair>();
foreach (var pair in (hl as HashLiteral).Pairs)
{
var key = Eval(pair.Key, env);
if (IsError(key))
{
return(key);
}
if (!(key is IHashable))
{
return new Error {
Message = "unusable as hashkey..."
}
}
;
var hashKey = key as IHashable;
var value = Eval(pair.Value, env);
if (IsError(value))
{
return(value);
}
var hashed = hashKey.HashKey();
pairs[hashed] = new HashPair()
{
Key = key, Value = value
};
}
return(new Hash()
{
Pairs = pairs
});
}
public IExpression Parse(Parser parser, Token token)
{
var hash = new HashLiteral
{
token = token,
Pairs = new Dictionary <IExpression, IExpression>()
};
while (!parser.PeekTokenIs(TokenType.RBRACE))
{
parser.NextToken();
var key = parser.ParseExpression(BindingPower.LOWEST);
if (!parser.ExpectPeek(TokenType.COLON))
{
return(null);
}
parser.NextToken();
var value = parser.ParseExpression(BindingPower.LOWEST);
hash.Pairs[key] = value;
if (!parser.PeekTokenIs(TokenType.RBRACE) && !parser.ExpectPeek(TokenType.COMMA))
{
return(null);
}
}
if (!parser.ExpectPeek(TokenType.RBRACE))
{
return(null);
}
return(hash);
}