public static StringExpression Analyze(Parsing.SAtom expr)
{
string text = expr.Text;
string literal = text.Substring(1, text.Length - 2); // Discards the opening & closing double quotes
return(new StringExpression(literal));
}
public void AddAndClearCache()
{
var symbol = new SAtom(cache.ToString());
stack.Peek().Add(symbol);
cache.Clear();
}
public static Variable Analyze(Parsing.SAtom expr)
{
if (Utils.IsValidIdentifier(expr.Text))
{
return(new Variable(expr.Text));
}
else
{
throw new BadSyntaxException("variable", "Invalid identifier", expr.Text);
}
}
public static Expression Analyze(Parsing.SAtom sExpr)
{
if (sExpr.Text == "#t")
{
return(new BooleanExpression(true));
}
else if (sExpr.Text == "#f")
{
return(new BooleanExpression(false));
}
// This case should have been intercepted before entering this function
else
{
throw new ArgumentException($"Unknown boolean literal: {sExpr.Text}");
}
}
public static bool IsInstance(Parsing.SAtom sExpr)
{
return(sExpr.Text == "#t" || sExpr.Text == "#f");
}
public static bool IsInstance(Parsing.SAtom expr)
{
string text = expr.Text;
return(text.Length >= 2 && text[0] == '\"' && text[text.Length - 1] == '\"');
}
public static bool IsInstance(Parsing.SAtom expr)
{
return(BigInteger.TryParse(expr.Text, out _));
}
public static NumberExpression Analyze(Parsing.SAtom expr)
{
return(new NumberExpression(expr.Text));
}