static ast.Expression parseHashLiteral()
{
ast.HashLiteral hash = new ast.HashLiteral {
Token = curToken
};
hash.Pairs = new Dictionary <ast.Expression, ast.Expression>();
while (!peekTokenIs(token.RBRACE))
{
nextToken();
ast.Expression key = parseExpression(LOWEST);
if (!expectPeek(token.COLON))
{
return(null);
}
nextToken();
ast.Expression value = parseExpression(LOWEST);
hash.Pairs.Add(key, value);
if (!peekTokenIs(token.RBRACE) && !expectPeek(token.COMMA))
{
return(null);
}
}
if (!expectPeek(token.RBRACE))
{
return(null);
}
return(hash);
}
static ast.Expression parseExpression(int precedence)
{
prefixParseFn prefix;
if (curToken.Type == null || !prefixParseFns.TryGetValue(curToken.Type, out prefix))
{
noPrefixFnError(curToken.Type);
return(null);
}
// stuff made static since saved tokens disappear from the scope of prefix()
ast.Expression leftExp = prefix();
while (!peekTokenIs(token.SEMICOLON) && precedence < peekPrecedence())
{
infixParseFn infix;
if (peekToken.Type == null || !infixParseFns.TryGetValue(peekToken.Type, out infix))
{
return(leftExp);
}
nextToken();
leftExp = infix(leftExp);
}
return(leftExp);
}
static ast.Expression parseCallExpression(ast.Expression function)
{
ast.CallExpression exp = new ast.CallExpression {
Token = curToken, Function = function
};
exp.Arguments = parseExpressionList(token.RPAREN);
return(exp);
}
static ast.Expression parseGroupedExpression()
{
nextToken();
ast.Expression exp = parseExpression(LOWEST);
if (!expectPeek(token.RPAREN))
{
return(null);
}
return(exp);
}
static ast.Expression parseIndexExpression(ast.Expression left)
{
ast.IndexExpression exp = new ast.IndexExpression {
Token = curToken, Left = left
};
nextToken();
exp.Index = parseExpression(LOWEST);
if (!expectPeek(token.RBRACKET))
{
return(null);
}
return(exp);
}
static ast.Expression parseInfixExpression(ast.Expression left)
{
ast.InfixExpression expression = new ast.InfixExpression
{
Token = curToken,
Operator = curToken.Literal,
Left = left
};
int precedence = curPrecedence();
nextToken();
expression.Right = parseExpression(precedence);
return(expression);
}